13232 + Interview Questions in Physics Page 29 InterviewSolution

1401.	How to calculate the centre of the curvature of a spherical mirror and a parabolic mirror
Answer» How to calculate the centre of the curvature of a spherical mirror and a parabolic mirror

Discussion

1402.	Question 69(i)The following graph shows the number of people present at a certain shop at different times. Observe the graph and answer the following questions.What type of a graph is this?
Answer» Question 69(i) The following graph shows the number of people present at a certain shop at different times. Observe the graph and answer the following questions. What type of a graph is this?

Discussion

1403.	A parallel plate capacitor of area 50cm2 and plate separation 3mm is charged initially to 80μC. Due to a radioactive source nearby, the medium between the plates gets slightly conducting and the plate loses charge initially at the rate of 1.5×10−8C/s. What is the magnitude and direction of displacement current?
Answer» A parallel plate capacitor of area 50cm2 and plate separation 3mm is charged initially to 80μC. Due to a radioactive source nearby, the medium between the plates gets slightly conducting and the plate loses charge initially at the rate of 1.5×10−8C/s. What is the magnitude and direction of displacement current?

Discussion

1404.	The motion of a body falling from rest in a mediumis given by equation dv/dt= 1-2v. The velocity atany time t is(1) (1 e)(2) (1 †extemdash е-)(1 e)(e)(1 e 2)(D)
Answer» The motion of a body falling from rest in a mediumis given by equation dv/dt= 1-2v. The velocity atany time t is(1) (1 e)(2) (1 †extemdash е-)(1 e)(e)(1 e 2)(D)

Discussion

1405.	What is meant by displacement?what is the unit of displacement?
Answer» What is meant by displacement?what is the unit of displacement?

Discussion

1406.	Aryan and Kevin are two friends. The mass of Aryan is 40 kg and the mass of Kevin is 50 kg. If they are 50 cm away from each other, then find the gravitational force (in N) acting between them. (G is the universal gravitational constant)
Answer» Aryan and Kevin are two friends. The mass of Aryan is 40 kg and the mass of Kevin is 50 kg. If they are 50 cm away from each other, then find the gravitational force (in N) acting between them. (G is the universal gravitational constant)

Discussion

1407.	If a bullet loses 1/20th of its velocity passing through 1 plank. Then how many planks are required to stop the bullet?
Answer» If a bullet loses 1/20th of its velocity passing through 1 plank. Then how many planks are required to stop the bullet?

Discussion

1408.	An Object is thrown into space with a of velocity 15 m/s at an angle oF GO 60° with respect to the horizontal, Calculate(1) maximum height(ii) time of flight(iii) horizontal range. (Given g = 9.8 m/s22. A ball is thrown into space with a velocity of 20 m/s at an angle of 45° with respect to the horizontal, Calculate(i) maximum height(ii) time of flight(iii) horizontal range. (Given g = 9.8 m/s-2)
Answer» An Object is thrown into space with a of velocity 15 m/s at an angle oF GO 60° with respect to the horizontal, Calculate (1) maximum height (ii) time of flight (iii) horizontal range. (Given g = 9.8 m/s2 2. A ball is thrown into space with a velocity of 20 m/s at an angle of 45° with respect to the horizontal, Calculate (i) maximum height (ii) time of flight (iii) horizontal range. (Given g = 9.8 m/s-2)

Discussion

1409.	Explain the working of an astronomical telescope using refraction of light.
Answer» Explain the working of an astronomical telescope using refraction of light.

Discussion

1410.	a bullet of mass 25 g is fired horizontally into a ballistic pendulum of mass 5.0 kg and gets embedded in it (figure 9-E14).If the centre of the pendulum rises by a distance of 10 cm,find the speed of the bullet.
Answer» a bullet of mass 25 g is fired horizontally into a ballistic pendulum of mass 5.0 kg and gets embedded in it (figure 9-E14).If the centre of the pendulum rises by a distance of 10 cm,find the speed of the bullet.

1410.

a bullet of mass 25 g is fired horizontally into a ballistic pendulum of mass 5.0 kg and gets embedded in it (figure 9-E14).If the centre of the pendulum rises by a distance of 10 cm,find the speed of the bullet.

Answer»

a bullet of mass 25 g is fired horizontally into a ballistic pendulum of mass 5.0 kg and gets embedded in it (figure 9-E14).If the centre of the pendulum rises by a distance of 10 cm,find the speed of the bullet.

Discussion

1411.	A ball at rest is dropped from the top of a mountain. What is the distance travelled by the ball in the first two seconds? ( Take acceleration due to gravity g=9.8ms−2)
Answer» A ball at rest is dropped from the top of a mountain. What is the distance travelled by the ball in the first two seconds? ( Take acceleration due to gravity $g = 9.8 m s^{- 2}$ )

Discussion

1412.

“Imagery” refers to something that can be perceived through more than one of the senses. It uses figurative language to help form mental pictures. Campbell used vivid, diverse and powerful imagery to personify the menacing face of nature (for e.g. sea, sky, wind, land). Pick out expressions that convey the images of anger in the following stanzas: Stanza 6 _______________ Stanza 7 ‘Water-wraith was shrieking’ _ Stanza 9 _ Stanza 10 _ ‘Stormy land’ Stanza 13 _ Stanza 14 _______________

Answer»

“Imagery”
refers to something that can be perceived through more than one of
the senses. It uses figurative language to help form mental pictures.
Campbell used vivid, diverse and powerful imagery to personify the
menacing face of nature (for e.g. sea, sky, wind, land). Pick out
expressions that convey the images of anger in the following stanzas:

Stanza 6	_______________________________
Stanza 7	‘Water-wraith was shrieking’
	_______________________________
Stanza 9	_______________________________
Stanza 10	_______________________________
	‘Stormy land’
Stanza 13	_______________________________
Stanza 14	_______________________________

Discussion

1413.	A Particle is moving in a circular path of radius r. The displacement after half a circle would be: (a) 0 (b) πr (c) 2r (d) 2πr
Answer» A Particle is moving in a circular path of radius r. The displacement after half a circle would be: (a) 0 (b) $π r$ (c) 2r (d) $2 π r$

1413.

A Particle is moving in a circular path of radius r. The displacement after half a circle would be: (a) 0 (b) πr (c) 2r (d) 2πr

Answer»

A Particle is moving in a circular path of radius r. The displacement after half a circle would be:

(a) 0

(b) $π r$

(c) 2r

(d) $2 π r$

Discussion

1414.	The distance travelled by a particle starting from rest and moving with an acceleration 4/3 ms-2 in the third second i
Answer» The distance travelled by a particle starting from rest and moving with an acceleration 4/3 ms-2 in the third second i

Discussion

1415.	Out of solids, liquids and gases : (a) in which medium sound travels slowest ? (b) in which medium sound travels fastest ?
Answer» Out of solids, liquids and gases : (a) in which medium sound travels slowest ? (b) in which medium sound travels fastest ?

1415.

Out of solids, liquids and gases : (a) in which medium sound travels slowest ? (b) in which medium sound travels fastest ?

Answer»

Out of solids, liquids and gases :

(a) in which medium sound travels slowest ?

(b) in which medium sound travels fastest ?

Discussion

1416.	In a parallel connection, the current has ______ path(s).
Answer» In a parallel connection, the current has ______ path(s).

Discussion

1417.	What will happen to the gravitational force between two body if they are closed by half of their initial separation
Answer» What will happen to the gravitational force between two body if they are closed by half of their initial separation

Discussion

1418.	a body is moving along a circular path of radius R what is the distance and displacement of a body when it completes 2 and half revolution
Answer» a body is moving along a circular path of radius R what is the distance and displacement of a body when it completes 2 and half revolution

Discussion

1419.	MnO_2 on ignition converts into Mn_3O_4. Asample of pyrolusite having 75 percent MnO_2 , 20 percent inert impurities and the rest water is ignited in air to cons†an t weight . What is the percentage of Mn in the ignited sample ?
Answer» MnO_2 on ignition converts into Mn_3O_4. Asample of pyrolusite having 75 percent MnO_2 , 20 percent inert impurities and the rest water is ignited in air to cons†an t weight . What is the percentage of Mn in the ignited sample ?

Discussion

1420.	What are the harmful effects of burning fossil fuels?
Answer» What are the harmful effects of burning fossil fuels?

Discussion

1421.	All the bulbs and cells used in the circuits are identical. If the switches are turned ON, in which of the following options will the bulb(s) be the brightest?
Answer» All the bulbs and cells used in the circuits are identical. If the switches are turned ON, in which of the following options will the bulb(s) be the brightest?

Discussion

1422.	The speed of a wave of time period T andpropagation constant K is (1) 2pi/TK (2) TK/2 pi (3) 1/TK (4) T/
Answer» The speed of a wave of time period T andpropagation constant K is (1) 2pi/TK (2) TK/2 pi (3) 1/TK (4) T/

Discussion

1423.	A charge 0.5 C passes through a cross section of a conductor in 5 seconds. Find the current flowing through the conductor.
Answer» A charge 0.5 C passes through a cross section of a conductor in 5 seconds. Find the current flowing through the conductor.

Discussion

1424.	Mass x change in velocity = ___ x time interval.
Answer» Mass x change in velocity = ___ x time interval.

Discussion

1425.	Give scientific reasons.a. When an object falls freely to the ground, its acceleration is uniform.b. Even though the magnitudes of action force and reaction force are equal and their directions are opposite, their effects do not get cancelled.c. It is easier to stop a tennis ball as compared to a cricket ball when both are travelling with the same velocity.d. The velocity of an object at rest is considered to be uniform.
Answer» Give scientific reasons. a. When an object falls freely to the ground, its acceleration is uniform. b. Even though the magnitudes of action force and reaction force are equal and their directions are opposite, their effects do not get cancelled. c. It is easier to stop a tennis ball as compared to a cricket ball when both are travelling with the same velocity. d. The velocity of an object at rest is considered to be uniform.

Discussion

1426.	A diver of 50 kg jumps from a platform 20 m high into a pool. If the diver decelerates at a constant rate to zero velocity in 0.8 seconds after hitting the water, what is the force that the water exerts on the diver? (g=10 ms−2)
Answer» A diver of $50 k g$ jumps from a platform $20 m$ high into a pool. If the diver decelerates at a constant rate to zero velocity in $0.8 s e c o n d s$ after hitting the water, what is the force that the water exerts on the diver? $(g = 10 m s^{- 2})$

Discussion

1427.	Two colestiai bodies are separated by some distance. it the mass of any one of the point likebodies is doubled wthile the mass of other is halved then how far shouid they be taken so thatthe gravitational force between them becomes one-fourth?8 By what percent will the gravitational force between the two bodies be increased if their massesare increased by 50%?
Answer» Two colestiai bodies are separated by some distance. it the mass of any one of the point likebodies is doubled wthile the mass of other is halved then how far shouid they be taken so thatthe gravitational force between them becomes one-fourth?8 By what percent will the gravitational force between the two bodies be increased if their massesare increased by 50%?

Discussion

1428.	Dust comes out of the carpet when it is beaten with a stick?
Answer» Dust comes out of the carpet when it is beaten with a stick?

Discussion

1429.	The gravitational force is quantitatively represented as:
Answer» The gravitational force is quantitatively represented as:

Discussion

1430.	A body at rest is made to fall from the top of a tower.Its displacement at different instants is given in the following table: Time (s)0.10.20.30.40.50.6Displacement (in m)0.050.200.450.801.251.80 Draw a displacement-time graph and state whether the motion is uniform or non-uniform ?
Answer» A body at rest is made to fall from the top of a tower.Its displacement at different instants is given in the following table: $\begin{matrix} T i m e (s) & 0.1 & 0.2 & 0.3 & 0.4 & 0.5 & 0.6 D i s p l a c e m e n t (i n m) & 0.05 & 0.20 & 0.45 & 0.80 & 1.25 & 1.80 \end{matrix}$ Draw a displacement-time graph and state whether the motion is uniform or non-uniform ?

1430.

A body at rest is made to fall from the top of a tower.Its displacement at different instants is given in the following table: Time (s)0.10.20.30.40.50.6Displacement (in m)0.050.200.450.801.251.80 Draw a displacement-time graph and state whether the motion is uniform or non-uniform ?

Answer»

A body at rest is made to fall from the top of a tower.Its displacement at different instants is given in the following table:

$\begin{matrix} T i m e (s) & 0.1 & 0.2 & 0.3 & 0.4 & 0.5 & 0.6 D i s p l a c e m e n t (i n m) & 0.05 & 0.20 & 0.45 & 0.80 & 1.25 & 1.80 \end{matrix}$

Draw a displacement-time graph and state whether the motion is uniform or non-uniform ?

Discussion

1431.	Lisa is walking in a peculiar fashion. She takes 5 steps forward and 3 steps backward, then again 5 forward and 3 backward and so on. If each step is of 1 m and takes 1 second to cover, then how much will she be displaced in 34 seconds from her initial position?
Answer» Lisa is walking in a peculiar fashion. She takes $5$ steps forward and $3$ steps backward, then again $5$ forward and $3$ backward and so on. If each step is of $1 m$ and takes $1$ second to cover, then how much will she be displaced in $34$ seconds from her initial position?

Discussion

1432.	Upthrust on a body is equal to ___.
Answer» Upthrust on a body is equal to ___.

Discussion

1433.	What are the amplitude and wavelength of the wave shown in the figure given below?
Answer» What are the amplitude and wavelength of the wave shown in the figure given below?

Discussion

1434.	A,B and C are voltmeters of resistance R,1.5R and 3R respectively. When some potential difference is applied between X and Y, the voltmeter readings are VA,VB and VC respectively. Then
Answer» $A, B$ and $C$ are voltmeters of resistance $R, 1.5 R$ and $3 R$ respectively. When some potential difference is applied between $X$ and $Y$ , the voltmeter readings are $V_{A}, V_{B}$ and $V_{C}$ respectively. Then

Discussion

1435.	20. A charged particle of specific charge(charge/mass) ? is released from orign at time t=0 wit velocity v=v (naught) ( i + j) in a uniform magnetic field B = B (naught) i . Coordiantes of the particle at time t= ?/B(naught).? are (1,2,3) then 1=? 2=? 3=?. Elaborate
Answer» 20. A charged particle of specific charge(charge/mass) ? is released from orign at time t=0 wit velocity v=v (naught) ( i + j) in a uniform magnetic field B = B (naught) i . Coordiantes of the particle at time t= ?/B(naught).? are (1,2,3) then 1=? 2=? 3=?. Elaborate

Discussion

1436.	What will be the angle of reflection if light falls normally on the reflecting surface?
Answer» What will be the angle of reflection if light falls normally on the reflecting surface?

Discussion

1437.	Identify the phenomenon relating to the images shown.
Answer» Identify the phenomenon relating to the images shown.

Discussion

1438.	4.what is the acceleration of an object moving in a circular path of radius r m with a uniform speed of v m/s
Answer» 4.what is the acceleration of an object moving in a circular path of radius r m with a uniform speed of v m/s

Discussion

1439.	Answer the questions by looking at the picture on the opposite page.Example : What is happening in picture 5?The girl is diving into the water.(i) What is Mohan practising in picture 4?He is ___________________________________________(ii) What are Anil and his friends pulling in picture 3?_________ are pulling ____________________________(iii) Where are the boats racing in picture 2?________ are ____________________________________(iv) What are the boys doing in picture 1?_______ are _____________________________________(v) What are the girls doing in picture 6?They are ________________________________________Disclaimer: Kindly refer the textbook for the images.
Answer» Answer the questions by looking at the picture on the opposite page. Example : What is happening in picture 5? The girl is diving into the water. (i) What is Mohan practising in picture 4? He is ___________________________________________ (ii) What are Anil and his friends pulling in picture 3? _________ are pulling ____________________________ (iii) Where are the boats racing in picture 2? ________ are ____________________________________ (iv) What are the boys doing in picture 1? _______ are _____________________________________ (v) What are the girls doing in picture 6? They are ________________________________________ Disclaimer: Kindly refer the textbook for the images.

Discussion

1440.	The resultant of balanced forces acting on an object is always _____.
Answer» The resultant of balanced forces acting on an object is always _____.

Discussion

1441.	Solve the following: A) An engine is moving with a velocity 44 m/s. After applying the brakes, it stops after covering a distance of 121 m. Calculate retardation and time taken by the engine to stop. B) A body starts from rest and moves with a constant acceleration. It travels a distance S1 in first 10s, and a distanceS2 in next 10s. Find the relation between S1 and S2. [5 MARKS]
Answer» Solve the following: A) An engine is moving with a velocity 44 m/s. After applying the brakes, it stops after covering a distance of 121 m. Calculate retardation and time taken by the engine to stop. B) A body starts from rest and moves with a constant acceleration. It travels a distance $S_{1}$ in first 10s, and a distance $S_{2}$ in next 10s. Find the relation between $S_{1}$ and $S_{2}$ . [5 MARKS]

Discussion

1442.	If the voltage of a source in an AC circuit is represented by the equation, E=220√2sin(314t). Calculate the peak value of the current if the net resistance of the circuit is 220 Ω. Take √2=1.4
Answer» If the voltage of a source in an AC circuit is represented by the equation, $E = 220 \sqrt{2} sin (314 t)$ . Calculate the peak value of the current if the net resistance of the circuit is $220 Ω$ . Take $\sqrt{2} = 1.4$

Discussion

1443.	There are two bodies A and B. 'A' has a positive charge whereas 'B' has no charge. When A and B are connected by a metallic wire, in what direction will the electrons flow?
Answer» There are two bodies A and B. 'A' has a positive charge whereas 'B' has no charge. When A and B are connected by a metallic wire, in what direction will the electrons flow?

Discussion

1444.	The resistance of the filament of a bulb ___ when it glows.
Answer» The resistance of the filament of a bulb ___ when it glows.

Discussion

1445.	two projectiles one fired from the surface of the earth with the speed 5m/s and other projected from the surface of the planet with initial speed 3m/s with some angle of project, trace identical trajectories neglecting friction effect the value of acceleration due to gravity on the planet is(a)5.9(b)3.5(c)16.3(d)7
Answer» two projectiles one fired from the surface of the earth with the speed 5m/s and other projected from the surface of the planet with initial speed 3m/s with some angle of project, trace identical trajectories neglecting friction effect the value of acceleration due to gravity on the planet is (a)5.9 (b)3.5 (c)16.3 (d)7

Discussion

1446.	What do the following measure in a car? (a) Speedometer (b) Odometer
Answer» What do the following measure in a car? (a) Speedometer (b) Odometer

1446.

What do the following measure in a car? (a) Speedometer (b) Odometer

Answer»

What do the following measure in a car?

(a) Speedometer
(b) Odometer

Discussion

1447.	a particle is moving in xy plane in a circular path with centre at origin . if at an ins†an t the position of particle is given by 1/\sqrt{2 }
Answer» a particle is moving in xy plane in a circular path with centre at origin . if at an ins†an t the position of particle is given by 1/\sqrt{2 }

Discussion

1448.	Is it important that displacement should be measured in a straight line?
Answer» Is it important that displacement should be measured in a straight line?

Discussion

1449.	In perfectly plastic body does restoring force exist?
Answer» In perfectly plastic body does restoring force exist?

Discussion

1450.	the resistance of a thin silver wire is 1 ohm at 20 degree centigrade. the wire is placed in a liquid bath and its resistance rises to 1.2 ohm. what is the temperature of the bath?in the solution ro is taken 1 ohm directly is it correct since ro is resistance at 0 degree centigrade
Answer» the resistance of a thin silver wire is 1 ohm at 20 degree centigrade. the wire is placed in a liquid bath and its resistance rises to 1.2 ohm. what is the temperature of the bath? in the solution ro is taken 1 ohm directly is it correct since ro is resistance at 0 degree centigrade

Discussion

Explore topic-wise InterviewSolutions in .

How to calculate the centre of the curvature of a spherical mirror and a parabolic mirror

Question 69(i)The following graph shows the number of people present at a certain shop at different times. Observe the graph and answer the following questions.What type of a graph is this?

The motion of a body falling from rest in a mediumis given by equation dv/dt= 1-2v. The velocity atany time t is(1) (1 e)(2) (1 †extemdash е-)(1 e)(e)(1 e 2)(D)

What is meant by displacement?what is the unit of displacement?

Aryan and Kevin are two friends. The mass of Aryan is 40 kg and the mass of Kevin is 50 kg. If they are 50 cm away from each other, then find the gravitational force (in N) acting between them. (G is the universal gravitational constant)

If a bullet loses 1/20th of its velocity passing through 1 plank. Then how many planks are required to stop the bullet?

Explain the working of an astronomical telescope using refraction of light.

a bullet of mass 25 g is fired horizontally into a ballistic pendulum of mass 5.0 kg and gets embedded in it (figure 9-E14).If the centre of the pendulum rises by a distance of 10 cm,find the speed of the bullet.

A ball at rest is dropped from the top of a mountain. What is the distance travelled by the ball in the first two seconds? ( Take acceleration due to gravity g=9.8ms−2)

A Particle is moving in a circular path of radius r. The displacement after half a circle would be: (a) 0 (b) πr (c) 2r (d) 2πr

The distance travelled by a particle starting from rest and moving with an acceleration 4/3 ms-2 in the third second i

Out of solids, liquids and gases : (a) in which medium sound travels slowest ? (b) in which medium sound travels fastest ?

In a parallel connection, the current has ______ path(s).

What will happen to the gravitational force between two body if they are closed by half of their initial separation

a body is moving along a circular path of radius R what is the distance and displacement of a body when it completes 2 and half revolution

MnO_2 on ignition converts into Mn_3O_4. Asample of pyrolusite having 75 percent MnO_2 , 20 percent inert impurities and the rest water is ignited in air to cons†an t weight . What is the percentage of Mn in the ignited sample ?

What are the harmful effects of burning fossil fuels?

All the bulbs and cells used in the circuits are identical. If the switches are turned ON, in which of the following options will the bulb(s) be the brightest?

The speed of a wave of time period T andpropagation constant K is (1) 2pi/TK (2) TK/2 pi (3) 1/TK (4) T/

A charge 0.5 C passes through a cross section of a conductor in 5 seconds. Find the current flowing through the conductor.

Mass x change in velocity = ___ x time interval.

A diver of 50 kg jumps from a platform 20 m high into a pool. If the diver decelerates at a constant rate to zero velocity in 0.8 seconds after hitting the water, what is the force that the water exerts on the diver? (g=10 ms−2)

Dust comes out of the carpet when it is beaten with a stick?

The gravitational force is quantitatively represented as:

A body at rest is made to fall from the top of a tower.Its displacement at different instants is given in the following table: Time (s)0.10.20.30.40.50.6Displacement (in m)0.050.200.450.801.251.80 Draw a displacement-time graph and state whether the motion is uniform or non-uniform ?

Lisa is walking in a peculiar fashion. She takes 5 steps forward and 3 steps backward, then again 5 forward and 3 backward and so on. If each step is of 1 m and takes 1 second to cover, then how much will she be displaced in 34 seconds from her initial position?

Upthrust on a body is equal to ___.

What are the amplitude and wavelength of the wave shown in the figure given below?

A,B and C are voltmeters of resistance R,1.5R and 3R respectively. When some potential difference is applied between X and Y, the voltmeter readings are VA,VB and VC respectively. Then

20. A charged particle of specific charge(charge/mass) ? is released from orign at time t=0 wit velocity v=v (naught) ( i + j) in a uniform magnetic field B = B (naught) i . Coordiantes of the particle at time t= ?/B(naught).? are (1,2,3) then 1=? 2=? 3=?. Elaborate

What will be the angle of reflection if light falls normally on the reflecting surface?

Identify the phenomenon relating to the images shown.

4.what is the acceleration of an object moving in a circular path of radius r m with a uniform speed of v m/s

The resultant of balanced forces acting on an object is always _____.

If the voltage of a source in an AC circuit is represented by the equation, E=220√2sin(314t). Calculate the peak value of the current if the net resistance of the circuit is 220 Ω. Take √2=1.4

There are two bodies A and B. 'A' has a positive charge whereas 'B' has no charge. When A and B are connected by a metallic wire, in what direction will the electrons flow?

The resistance of the filament of a bulb ___ when it glows.

What do the following measure in a car? (a) Speedometer (b) Odometer

a particle is moving in xy plane in a circular path with centre at origin . if at an ins†an t the position of particle is given by 1/\sqrt{2 }

Is it important that displacement should be measured in a straight line?

In perfectly plastic body does restoring force exist?

the resistance of a thin silver wire is 1 ohm at 20 degree centigrade. the wire is placed in a liquid bath and its resistance rises to 1.2 ohm. what is the temperature of the bath?in the solution ro is taken 1 ohm directly is it correct since ro is resistance at 0 degree centigrade