50278 + Interview Questions in Physics Page 244 InterviewSolution

12151.	Question 14A bullet of mass 10 g travelling horizontally with a velocity of 150 ms−1 strikes a stationary wooden block and comes to rest in 0.03 s. Calculate the distance of penetration of the bullet into the block. Also calculate the magnitude of the force exerted by the wooden block on the bullet.
Answer» Question 14 A bullet of mass 10 g travelling horizontally with a velocity of $150 m s^{- 1}$ strikes a stationary wooden block and comes to rest in 0.03 s. Calculate the distance of penetration of the bullet into the block. Also calculate the magnitude of the force exerted by the wooden block on the bullet.

Discussion

12152.	Rain is falling vertically with a speed of 30 m s¯¹. A woman rides a bicycle with a speed of 10 m s¯¹ in the north to south direction. What is the direction in which she should hold her umbrella ?
Answer» Rain is falling vertically with a speed of 30 m s¯¹. A woman rides a bicycle with a speed of 10 m s¯¹ in the north to south direction. What is the direction in which she should hold her umbrella ?

Discussion

12153.	Two 550 kVA alternators operate in parallel to supply the following loads:(i) 250 kW at 0.6 p.f lagging(ii) 100 kW at 0.5 p.f. leadingIf one machine supply 200 kW at 0.9 p.f lagging, the p.f. of other machine is _____ lagging.0.92
Answer» Two 550 kVA alternators operate in parallel to supply the following loads: (i) 250 kW at 0.6 p.f lagging (ii) 100 kW at 0.5 p.f. leading If one machine supply 200 kW at 0.9 p.f lagging, the p.f. of other machine is _____ lagging. 0.92

Discussion

12154.	Q 10/15 A disc of mass 1 kg and radius 0.2 m is rotating with angular velocity 40 rad/s. What is angular velocity (in rad/s), if a mass of 0.5 kg is put on the circumference of the disc? 2 rad/s 4 rad/s 20 rad/s 40 3 rad/s
Answer» Q 10/15 A disc of mass 1 kg and radius 0.2 m is rotating with angular velocity 40 rad/s. What is angular velocity (in rad/s), if a mass of 0.5 kg is put on the circumference of the disc? 2 rad/s 4 rad/s 20 rad/s 40 3 rad/s

Discussion

12155.	three parallel metallic plates each of area a are kept apart and charges Q1,Q2,Q3are given to them.effect edges are negligible.calculate the charges on the two outermost surfaces of the parallel plate capacitor
Answer» three parallel metallic plates each of area a are kept apart and charges Q1,Q2,Q3are given to them.effect edges are negligible.calculate the charges on the two outermost surfaces of the parallel plate capacitor

Discussion

12156.	2. A long straight wire carries a current i. A particle having a positive charge q amd mass m kept at a distance x from the wire is projected towards it with a speed v. Find the minimum separation between the wire and the particle ??
Answer» 2. A long straight wire carries a current i. A particle having a positive charge q amd mass m kept at a distance x from the wire is projected towards it with a speed v. Find the minimum separation between the wire and the particle ??

Discussion

12157.	The angular momentum of an electron in an orbit having the highest magnetic quantum number 2, is:
Answer» The angular momentum of an electron in an orbit having the highest magnetic quantum number 2, is:

Discussion

12158.	Two identical narrow slits S1 and S2 are illuminated by light of wavelength λ from a point source P as shown in the figure. The light is then allowed to fall on a screen, and if n is a positive integer, then the condition for destructive interference at Q is-
Answer» Two identical narrow slits $S_{1}$ and $S_{2}$ are illuminated by light of wavelength $λ$ from a point source $P$ as shown in the figure. The light is then allowed to fall on a screen, and if $n$ is a positive integer, then the condition for destructive interference at $Q$ is-

Discussion

12159.	Two unequal masses of 1 kg and 2 kg are connected by an inextensible light string passing over a smooth pulley as shown in figure. A force F=20 N is applied on 1 kg block. Find the magnitude of acceleration of either block. (g=10 m/s2)
Answer» Two unequal masses of $1 kg$ and $2 kg$ are connected by an inextensible light string passing over a smooth pulley as shown in figure. A force $F = 20 N$ is applied on $1 kg$ block. Find the magnitude of acceleration of either block. ( $g = 10 {m/s}^{2}$ )

Discussion

12160.	A particle 'm' starts with zero velocity along a line y = 4d. (Where d is a constant). The position of particle 'm' varies as x = A sin ωt. At ωt = π2, its angular momentum with respect to the origin is?
Answer» A particle ' $m$ ' starts with zero velocity along a line $y$ = $4 d$ . (Where $d$ is a constant). The position of particle ' $m$ ' varies as $x$ = $A s i n ω t$ . At $ω t$ = $\frac{π}{2}$ , its angular momentum with respect to the origin is?

12160.

A particle 'm' starts with zero velocity along a line y = 4d. (Where d is a constant). The position of particle 'm' varies as x = A sin ωt. At ωt = π2, its angular momentum with respect to the origin is?

Answer»

A particle ' $m$ ' starts with zero velocity along a line $y$ = $4 d$ . (Where $d$ is a constant). The position of particle ' $m$ ' varies as $x$ = $A s i n ω t$ . At $ω t$ = $\frac{π}{2}$ , its angular momentum with respect to the origin is?

Discussion

12161.	66.The electric field energy in a capacitor changes from maximum to minimum value in 2.5ms when connected to a AC source. The frequency of the source is
Answer» 66.The electric field energy in a capacitor changes from maximum to minimum value in 2.5ms when connected to a AC source. The frequency of the source is

Discussion

12162.	5.N identical bulbs each designed to draw power P from certain voltage supply are joined in series across that supply. The total power which they will draw ?
Answer» 5.N identical bulbs each designed to draw power P from certain voltage supply are joined in series across that supply. The total power which they will draw ?

Discussion

12163.	Emulsification of 10mL of oil in water produces 2.4× 10^16 droplets if the surface tension at the oil water interface is 0.03 Jm^-3 and the area of each droplet is 12.5 × 10^18 m^2 the energy spent in the formation of droplet isOptions(1) 90J(2) 30J(3) 900J(4) 10J
Answer» Emulsification of 10mL of oil in water produces 2.4× 10^16 droplets if the surface tension at the oil water interface is 0.03 Jm^-3 and the area of each droplet is 12.5 × 10^18 m^2 the energy spent in the formation of droplet is Options (1) 90J (2) 30J (3) 900J (4) 10J

Discussion

12164.	A plastic circular disc of radius R is placed on a thin oil film, spread over a flat horizontal surface. The torque required to spin the disc about its central vertical axis with a constant angular velocity is proportional to :
Answer» A plastic circular disc of radius $R$ is placed on a thin oil film, spread over a flat horizontal surface. The torque required to spin the disc about its central vertical axis with a constant angular velocity is proportional to :

Discussion

12165.	A cylindrical tank of height H is completely filled with water. On its vertical side, there are two tiny holes, one above the middle at a height of h1 and other below the middle at a depth of h2. If the jets of water from the holes meet at the same point on the ground, then the ratio h1h2 is
Answer» A cylindrical tank of height $H$ is completely filled with water. On its vertical side, there are two tiny holes, one above the middle at a height of $h_{1}$ and other below the middle at a depth of $h_{2}$ . If the jets of water from the holes meet at the same point on the ground, then the ratio $\frac{h_{1}}{h_{2}}$ is

Discussion

12166.	A force →F=(^i+2^j) N acts at O, the origin of the co-ordinate system. The torque about the point (1,–1,1) m is
Answer» A force $\to F = (^i + 2^j) N$ acts at $O$ , the origin of the co-ordinate system. The torque about the point $(1, - 1, 1) m$ is

Discussion

12167.	A uniform circular disc of radius 50cm at rest is free to turn about an axis which is perpendicular to its plane and passes through its centre. It is subjected to a torque which produces a const. angular acceleration of 2 rad per sec sq. Its net acceleration in m/ s^2 at the end of 2 s is
Answer» A uniform circular disc of radius 50cm at rest is free to turn about an axis which is perpendicular to its plane and passes through its centre. It is subjected to a torque which produces a const. angular acceleration of 2 rad per sec sq. Its net acceleration in m/ s^2 at the end of 2 s is

Discussion

12168.	six equal positive charge q are placed at the vertices of regular hexagon of side a the charge are kept at the centre of the hexagonn for equilibrium of sysyem i
Answer» six equal positive charge q are placed at the vertices of regular hexagon of side a the charge are kept at the centre of the hexagonn for equilibrium of sysyem i

Discussion

12169.	If two identical spheres having charges 4 μC and –2 μC are kept at certain distance apart, have force F between them. They are touched and again kept at same distance, the force becomes?
Answer» If two identical spheres having charges 4 μC and –2 μC are kept at certain distance apart, have force F between them. They are touched and again kept at same distance, the force becomes?

Discussion

12170.	The mass of a photo electron is
Answer» The mass of a photo electron is

Discussion

12171.	Look at the graphs (a) to (d) (Fig. 3.20) carefully and state, with reasons, which of these cannot possibly represent one-dimensional motion of a particle.
Answer» Look at the graphs (a) to (d) (Fig. 3.20) carefully and state, with reasons, which of these cannot possibly represent one-dimensional motion of a particle.

Discussion

12172.	The moment of inertia of the uniform rod of length and ‘2m’ about an axis through centre and inclined at an angle 30° with length of the rod will be
Answer» The moment of inertia of the uniform rod of length and ‘2m’ about an axis through centre and inclined at an angle 30° with length of the rod will be

Discussion

12173.	A body of mass (M) 10 kg is initially stationary on a 45° inclined plane as shown in figure. The coefficient of dynamic friction between the body and the plane is 0.5. The body slides down the plane and attains a velocity of 20 m/s. The distance travelled (in meter) by the body along the plane is
Answer» A body of mass (M) 10 kg is initially stationary on a 45° inclined plane as shown in figure. The coefficient of dynamic friction between the body and the plane is 0.5. The body slides down the plane and attains a velocity of 20 m/s. The distance travelled (in meter) by the body along the plane is

Discussion

12174.	What is the shortest wavelength present in the radiation of an X-ray machine whose accelerating potential is 50,000 V?
Answer» What is the shortest wavelength present in the radiation of an X-ray machine whose accelerating potential is $50, 000 V$ ?

Discussion

12175.	What is the percentage increase in the linear momentum if the kinetic energy of the body is increased by 800 percent?
Answer» What is the percentage increase in the linear momentum if the kinetic energy of the body is increased by 800 percent?

Discussion

12176.	45.The horizontal range and maximum height of a projectile are equal. The angle of projection of the projectile is
Answer» 45.The horizontal range and maximum height of a projectile are equal. The angle of projection of the projectile is

Discussion

12177.	Four equal charges q each are placed at four corners of a square of side 'a' each. Then what will be the workdone in carrying a charge -q from its centre to infinity?
Answer» Four equal charges q each are placed at four corners of a square of side 'a' each. Then what will be the workdone in carrying a charge -q from its centre to infinity?

Discussion

12178.	If a copper wire is stretched to make its cross sectional radius 0.1% thinner,then what is % increase in its resistence?
Answer» If a copper wire is stretched to make its cross sectional radius 0.1% thinner,then what is % increase in its resistence?

Discussion

12179.	The electric potential decreases uniformly from 100V to 50V as one moves along the x-axis from x=0 to x=5m.The electric field at x=2m must be equal to 10V/m.Is this statement true or false.
Answer» The electric potential decreases uniformly from 100V to 50V as one moves along the x-axis from x=0 to x=5m.The electric field at x=2m must be equal to 10V/m.Is this statement true or false.

Discussion

12180.	16.The length of a vertical stick at the surface of a lake appears 12 cm to a fish under water. if refractive index of water is 4/3 , then actual length of stick above water surface is
Answer» 16.The length of a vertical stick at the surface of a lake appears 12 cm to a fish under water. if refractive index of water is 4/3 , then actual length of stick above water surface is

Discussion

12181.	Study the following graph carefully and answer the questions that follow. Consumption of two metals in the given years by a company (in '000 tones) Q42. In how many years, the consumption of metal A was less than the average consumption of metal B in the given years?
Answer» Study the following graph carefully and answer the questions that follow. Consumption of two metals in the given years by a company (in '000 tones) Q42. In how many years, the consumption of metal A was less than the average consumption of metal B in the given years?

12181.

Study the following graph carefully and answer the questions that follow. Consumption of two metals in the given years by a company (in '000 tones) Q42. In how many years, the consumption of metal A was less than the average consumption of metal B in the given years?

Answer»

Study the following graph carefully and answer the questions that follow. Consumption of two metals in the given years by a company (in '000 tones)

Q42. In how many years, the consumption of metal A was less than the average consumption of metal B in the given years?

Discussion

12182.	In Young's double slit experiment the y-coordinates of central maxima and 10th maxima are 2 cm and 5 cm respectively. When the YDSE apparatus is immersed in a liquid of refractive index 1.5 the corresponding y-coordinates will be
Answer» In Young's double slit experiment the y-coordinates of central maxima and 10th maxima are 2 cm and 5 cm respectively. When the YDSE apparatus is immersed in a liquid of refractive index 1.5 the corresponding y-coordinates will be

Discussion

12183.	Just as electricity is supplied at 220V in India, it is supplied 110 V in USA. If the resistance of 60W bulb for use in India is R, that of a 60W bulb for use in USA will be
Answer» Just as electricity is supplied at 220V in India, it is supplied 110 V in USA. If the resistance of 60W bulb for use in India is R, that of a 60W bulb for use in USA will be

Discussion

12184.	The orbital velocity of a satellite at point B with radius rB is v. The radius of point A is rA.When satellite is at A, the orbit is increased in radial distances uniformly, so that rA becomes 1.2rA , find the orbital velocity at (1.2rA)
Answer» The orbital velocity of a satellite at point $B$ with radius $r_{B}$ is $v$ . The radius of point $A$ is $r_{A}$ .When satellite is at $A$ , the orbit is increased in radial distances uniformly, so that $r_{A}$ becomes $1.2 r_{A}$ , find the orbital velocity at $(1.2 r_{A})$

Discussion

12185.	The Fourier transform of the below function is
Answer» The Fourier transform of the below function is

Discussion

12186.	Two bulbs A and B rated 200 V~100W and 200V~60 W are connected in series to 200 V line. Then prove that the potential drop across 100W bulb is smallerthan that across 60 W bulb.
Answer» Two bulbs A and B rated 200 V~100W and 200V~60 W are connected in series to 200 V line. Then prove that the potential drop across 100W bulb is smallerthan that across 60 W bulb.

Discussion

12187.	Charges 5×10−7 C,−2.5×10−7 C and 1×10−7 C are held fixed at the three corners A,B and C of an equilateral triangle of side 10 cm respectively. Find the electric force on the charge at C due to the rest two (correct answer + 1, wrong answer - 0.25)
Answer» Charges $5 \times 10^{- 7} C, - 2.5 \times 10^{- 7} C$ and $1 \times 10^{- 7} C$ are held fixed at the three corners $A, B$ and $C$ of an equilateral triangle of side $10 cm$ respectively. Find the electric force on the charge at $C$ due to the rest two (correct answer + 1, wrong answer - 0.25)

Discussion

12188.	the de -broglie wavelength of a particle moving with a velocity 2.25* 10^8 m/s is equal to the wavelength of photon .the ratio of kinetic energy of the particle to the energy of the photon isA)1/8b)3/8c)5/8d)7/8
Answer» the de -broglie wavelength of a particle moving with a velocity 2.25* 10^8 m/s is equal to the wavelength of photon .the ratio of kinetic energy of the particle to the energy of the photon is A)1/8 b)3/8 c)5/8 d)7/8

Discussion

12189.	A stone of mass 50 g thrown vertically upward witha speed of 30 m/s reaches to a maximum heightof 25 m. The magnitude of average frictional forceexerted by air during upward journey is
Answer» A stone of mass 50 g thrown vertically upward with a speed of 30 m/s reaches to a maximum height of 25 m. The magnitude of average frictional force exerted by air during upward journey is

Discussion

12190.	An ideal diesel engine has a diameter (bore) of 15 cm and stroke 20 cm. The clearance volume is 10 percent of the swept volume. If the cut-off takes place at 5 percent of the stroke, the air standard efficiency of the engine is _____%.58.168
Answer» An ideal diesel engine has a diameter (bore) of 15 cm and stroke 20 cm. The clearance volume is 10 percent of the swept volume. If the cut-off takes place at 5 percent of the stroke, the air standard efficiency of the engine is _____%. 58.168

Discussion

12191.	A bullet is fired vertically upwards with velocity v from the surface of a spherical planet. When it reaches its maximum height, its acceleration due to the planet's gravity is 14th of its value at the surface of the planet. If the escape velocity from the planet is v0=v√N, then the value of N is [ignore energy loss due to atmosphere]
Answer» A bullet is fired vertically upwards with velocity $v$ from the surface of a spherical planet. When it reaches its maximum height, its acceleration due to the planet's gravity is $\frac{1}{4}$ th of its value at the surface of the planet. If the escape velocity from the planet is $v_{0} = v \sqrt{N}$ , then the value of $N$ is [ignore energy loss due to atmosphere]

Discussion

12192.	The ratio of surface tensions of mercury and water is given to be 7.5 while the ratio of their densities is 13.6. Their contact angles, with glass, are close to 135° and 0°, respectively. It is observed that mercury gets depressed by an amount h in a capillary tube of radius r1, while water rises by the same amount h in a capillary tube of radius r2. The ratio, (r1r2), is then close to
Answer» The ratio of surface tensions of mercury and water is given to be $7.5$ while the ratio of their densities is $13.6$ . Their contact angles, with glass, are close to $135 °$ and $0 °$ , respectively. It is observed that mercury gets depressed by an amount $h$ in a capillary tube of radius $r_{1}$ , while water rises by the same amount $h$ in a capillary tube of radius $r_{2}$ . The ratio, $(\frac{r_{1}}{r_{2}})$ , is then close to

Discussion

12193.	The sign of work done by a force on a body is important to understand. State carefully if the following quantities are positive or negative: (a) work done by a man in lifting a bucket out of a well by means of a rope tied to the bucket. (b) work done by gravitational force in the above case, (c) work done by friction on a body sliding down an inclined plane, (d) work done by an applied force on a body moving on a rough horizontal plane with uniform velocity, (e) work done by the resistive force of air on a vibrating pendulum in bringing it to rest.
Answer» The sign of work done by a force on a body is important to understand. State carefully if the following quantities are positive or negative: (a) work done by a man in lifting a bucket out of a well by means of a rope tied to the bucket. (b) work done by gravitational force in the above case, (c) work done by friction on a body sliding down an inclined plane, (d) work done by an applied force on a body moving on a rough horizontal plane with uniform velocity, (e) work done by the resistive force of air on a vibrating pendulum in bringing it to rest.

Discussion

12194.	38.Three point charges each of charge q are placed at three corners of an equilateral triangle of side a .The electric potential at centre will be
Answer» 38.Three point charges each of charge q are placed at three corners of an equilateral triangle of side a .The electric potential at centre will be

Discussion

12195.	The range of projectile is R when the angle of projection is 55∘. For the same velocity of projection and range, the other possible angle of projection is
Answer» The range of projectile is $R$ when the angle of projection is $55^{\circ}$ . For the same velocity of projection and range, the other possible angle of projection is

Discussion

12196.	Find the electric field at a point P on the perpendicular bisector of a uniformly charged rod. The length of the rod is L, the charge on it is Q and the distance of P from centre is a.
Answer» Find the electric field at a point P on the perpendicular bisector of a uniformly charged rod. The length of the rod is L, the charge on it is Q and the distance of P from centre is a.

Discussion

12197.	A motorboat going downstream overcame a raft at a point A; t = 60 minutes later, it turned back and after some time passed the raft at a distance l = 6.0 km from the point A. Find the flow velocity assuming the duty of the engine to be constant.
Answer» A motorboat going downstream overcame a raft at a point A; t = 60 minutes later, it turned back and after some time passed the raft at a distance l = 6.0 km from the point A. Find the flow velocity assuming the duty of the engine to be constant.

Discussion

12198.	Why electrostatic potential decreases in the direction of electric field?
Answer» Why electrostatic potential decreases in the direction of electric field?

Discussion

12199.	For a concave mirror, if real image is formed the graph between is of the form
Answer» For a concave mirror, if real image is formed the graph between is of the form

Discussion

12200.	two motor cars starting off with a time gap of 2 minute, travel in the same direction with the same acceleration. time taken by the second car since its departure to complete (1/9)th of the distance covered by the first car is
Answer» two motor cars starting off with a time gap of 2 minute, travel in the same direction with the same acceleration. time taken by the second car since its departure to complete (1/9)th of the distance covered by the first car is

Discussion

Explore topic-wise InterviewSolutions in .

Rain is falling vertically with a speed of 30 m s¯¹. A woman rides a bicycle with a speed of 10 m s¯¹ in the north to south direction. What is the direction in which she should hold her umbrella ?

Two 550 kVA alternators operate in parallel to supply the following loads:(i) 250 kW at 0.6 p.f lagging(ii) 100 kW at 0.5 p.f. leadingIf one machine supply 200 kW at 0.9 p.f lagging, the p.f. of other machine is _____ lagging.0.92

Q 10/15 A disc of mass 1 kg and radius 0.2 m is rotating with angular velocity 40 rad/s. What is angular velocity (in rad/s), if a mass of 0.5 kg is put on the circumference of the disc? 2 rad/s 4 rad/s 20 rad/s 40 3 rad/s

three parallel metallic plates each of area a are kept apart and charges Q1,Q2,Q3are given to them.effect edges are negligible.calculate the charges on the two outermost surfaces of the parallel plate capacitor

2. A long straight wire carries a current i. A particle having a positive charge q amd mass m kept at a distance x from the wire is projected towards it with a speed v. Find the minimum separation between the wire and the particle ??

The angular momentum of an electron in an orbit having the highest magnetic quantum number 2, is:

Two identical narrow slits S1 and S2 are illuminated by light of wavelength λ from a point source P as shown in the figure. The light is then allowed to fall on a screen, and if n is a positive integer, then the condition for destructive interference at Q is-

Two unequal masses of 1 kg and 2 kg are connected by an inextensible light string passing over a smooth pulley as shown in figure. A force F=20 N is applied on 1 kg block. Find the magnitude of acceleration of either block. (g=10 m/s2)

A particle 'm' starts with zero velocity along a line y = 4d. (Where d is a constant). The position of particle 'm' varies as x = A sin ωt. At ωt = π2, its angular momentum with respect to the origin is?

66.The electric field energy in a capacitor changes from maximum to minimum value in 2.5ms when connected to a AC source. The frequency of the source is

5.N identical bulbs each designed to draw power P from certain voltage supply are joined in series across that supply. The total power which they will draw ?

Emulsification of 10mL of oil in water produces 2.4× 10^16 droplets if the surface tension at the oil water interface is 0.03 Jm^-3 and the area of each droplet is 12.5 × 10^18 m^2 the energy spent in the formation of droplet isOptions(1) 90J(2) 30J(3) 900J(4) 10J

A plastic circular disc of radius R is placed on a thin oil film, spread over a flat horizontal surface. The torque required to spin the disc about its central vertical axis with a constant angular velocity is proportional to :

A cylindrical tank of height H is completely filled with water. On its vertical side, there are two tiny holes, one above the middle at a height of h1 and other below the middle at a depth of h2. If the jets of water from the holes meet at the same point on the ground, then the ratio h1h2 is

A force →F=(^i+2^j) N acts at O, the origin of the co-ordinate system. The torque about the point (1,–1,1) m is

A uniform circular disc of radius 50cm at rest is free to turn about an axis which is perpendicular to its plane and passes through its centre. It is subjected to a torque which produces a const. angular acceleration of 2 rad per sec sq. Its net acceleration in m/ s^2 at the end of 2 s is

six equal positive charge q are placed at the vertices of regular hexagon of side a the charge are kept at the centre of the hexagonn for equilibrium of sysyem i

If two identical spheres having charges 4 μC and –2 μC are kept at certain distance apart, have force F between them. They are touched and again kept at same distance, the force becomes?

The mass of a photo electron is

Look at the graphs (a) to (d) (Fig. 3.20) carefully and state, with reasons, which of these cannot possibly represent one-dimensional motion of a particle.

The moment of inertia of the uniform rod of length and ‘2m’ about an axis through centre and inclined at an angle 30° with length of the rod will be

A body of mass (M) 10 kg is initially stationary on a 45° inclined plane as shown in figure. The coefficient of dynamic friction between the body and the plane is 0.5. The body slides down the plane and attains a velocity of 20 m/s. The distance travelled (in meter) by the body along the plane is

What is the shortest wavelength present in the radiation of an X-ray machine whose accelerating potential is 50,000 V?

What is the percentage increase in the linear momentum if the kinetic energy of the body is increased by 800 percent?

45.The horizontal range and maximum height of a projectile are equal. The angle of projection of the projectile is

Four equal charges q each are placed at four corners of a square of side 'a' each. Then what will be the workdone in carrying a charge -q from its centre to infinity?

If a copper wire is stretched to make its cross sectional radius 0.1% thinner,then what is % increase in its resistence?

The electric potential decreases uniformly from 100V to 50V as one moves along the x-axis from x=0 to x=5m.The electric field at x=2m must be equal to 10V/m.Is this statement true or false.

16.The length of a vertical stick at the surface of a lake appears 12 cm to a fish under water. if refractive index of water is 4/3 , then actual length of stick above water surface is

Study the following graph carefully and answer the questions that follow. Consumption of two metals in the given years by a company (in '000 tones) Q42. In how many years, the consumption of metal A was less than the average consumption of metal B in the given years?

In Young's double slit experiment the y-coordinates of central maxima and 10th maxima are 2 cm and 5 cm respectively. When the YDSE apparatus is immersed in a liquid of refractive index 1.5 the corresponding y-coordinates will be

Just as electricity is supplied at 220V in India, it is supplied 110 V in USA. If the resistance of 60W bulb for use in India is R, that of a 60W bulb for use in USA will be

The orbital velocity of a satellite at point B with radius rB is v. The radius of point A is rA.When satellite is at A, the orbit is increased in radial distances uniformly, so that rA becomes 1.2rA , find the orbital velocity at (1.2rA)

The Fourier transform of the below function is

Two bulbs A and B rated 200 V~100W and 200V~60 W are connected in series to 200 V line. Then prove that the potential drop across 100W bulb is smallerthan that across 60 W bulb.

Charges 5×10−7 C,−2.5×10−7 C and 1×10−7 C are held fixed at the three corners A,B and C of an equilateral triangle of side 10 cm respectively. Find the electric force on the charge at C due to the rest two (correct answer + 1, wrong answer - 0.25)

the de -broglie wavelength of a particle moving with a velocity 2.25* 10^8 m/s is equal to the wavelength of photon .the ratio of kinetic energy of the particle to the energy of the photon isA)1/8b)3/8c)5/8d)7/8

A stone of mass 50 g thrown vertically upward witha speed of 30 m/s reaches to a maximum heightof 25 m. The magnitude of average frictional forceexerted by air during upward journey is

An ideal diesel engine has a diameter (bore) of 15 cm and stroke 20 cm. The clearance volume is 10 percent of the swept volume. If the cut-off takes place at 5 percent of the stroke, the air standard efficiency of the engine is _____%.58.168

38.Three point charges each of charge q are placed at three corners of an equilateral triangle of side a .The electric potential at centre will be

The range of projectile is R when the angle of projection is 55∘. For the same velocity of projection and range, the other possible angle of projection is

Find the electric field at a point P on the perpendicular bisector of a uniformly charged rod. The length of the rod is L, the charge on it is Q and the distance of P from centre is a.

A motorboat going downstream overcame a raft at a point A; t = 60 minutes later, it turned back and after some time passed the raft at a distance l = 6.0 km from the point A. Find the flow velocity assuming the duty of the engine to be constant.

Why electrostatic potential decreases in the direction of electric field?

For a concave mirror, if real image is formed the graph between is of the form

two motor cars starting off with a time gap of 2 minute, travel in the same direction with the same acceleration. time taken by the second car since its departure to complete (1/9)th of the distance covered by the first car is