13232 + Interview Questions in Physics Page 38 InterviewSolution

1851.	A key falls from a bridge that is 45 m above the water. It falls directly into a model boat, moving with constant velocity, that is 12 m from the point of impact when the key is released. The speed of the boat is1 ) 2m/s 2 ) 4m/s3 ) 9m/s 4 ) 48m/s
Answer» A key falls from a bridge that is 45 m above the water. It falls directly into a model boat, moving with constant velocity, that is 12 m from the point of impact when the key is released. The speed of the boat is 1 ) 2m/s 2 ) 4m/s 3 ) 9m/s 4 ) 48m/s

Discussion

1852.	Question 62(i)The graph given below compares the sales of ice-creams of two vendors for a week.Observe the graph and answer the following question.Which vendor has sold more ice-creams on Friday?
Answer» Question 62(i) The graph given below compares the sales of ice-creams of two vendors for a week. Observe the graph and answer the following question. Which vendor has sold more ice-creams on Friday?

Discussion

1853.	If a car travels first 40km at speed of 20km/h and next 80km at a speed of 40km/h. What is the average speed of car for entire journey?
Answer» If a car travels first 40km at speed of 20km/h and next 80km at a speed of 40km/h. What is the average speed of car for entire journey?

Discussion

1854.	A swimmer crosses the river along the line making an angle 135^° with the direction of flow. Velocity of the river is 5 m/s. Swimmer takes 10 seconds to cross the river of width 100 m. The velocity of swimmer with respect to water will be
Answer» A swimmer crosses the river along the line making an angle 135^° with the direction of flow. Velocity of the river is 5 m/s. Swimmer takes 10 seconds to cross the river of width 100 m. The velocity of swimmer with respect to water will be

Discussion

1855.	Anita was driving at a speed of 85.6 km per hour. The road had a speed limit of 55 km per hour. By how much should she reduce her speed to be within the speed limit?
Answer» Anita was driving at a speed of 85.6 km per hour. The road had a speed limit of 55 km per hour. By how much should she reduce her speed to be within the speed limit?

Discussion

1856.	Calculate the mass of a charged particle in CGS units if its charge is X coloumb and specific charge is y coulomb /g
Answer» Calculate the mass of a charged particle in CGS units if its charge is X coloumb and specific charge is y coulomb /g

Discussion

1857.	A spring of spring constant k suspends a block of mass m, find the maximum elongation of the spring when block is released from rest.
Answer» A spring of spring constant k suspends a block of mass m, find the maximum elongation of the spring when block is released from rest.

Discussion

1858.	19. A satellite is revolving around earth in a circular orbit at a uniform speed v. If gravitational force suddenlydisappears, speed of the satellite will be(1) Zero(2)V(3)2V(4) Infinity
Answer» 19. A satellite is revolving around earth in a circular orbit at a uniform speed v. If gravitational force suddenly disappears, speed of the satellite will be (1) Zero (2) V (3) 2V (4) Infinity

Discussion

1859.	Does the speed of an object change if the frame of reference changes?
Answer» Does the speed of an object change if the frame of reference changes?

Discussion

1860.	Which of the following statements is correct about a freely falling body?1. Total energy is constant.2. Potential energy changes into kinetic energy.3. Potential energy decreases.4. Kinetic energy increases.
Answer» Which of the following statements is correct about a freely falling body? 1. Total energy is constant. 2. Potential energy changes into kinetic energy. 3. Potential energy decreases. 4. Kinetic energy increases.

Discussion

1861.	if we throw an object horizontally and other vertically downward direction from same height.calculat time taken ,velocity of strike on ground ,time of flight for both situations?
Answer» if we throw an object horizontally and other vertically downward direction from same height.calculat time taken ,velocity of strike on ground ,time of flight for both situations?

Discussion

1862.	what is a relativistic charged particle ?Explain the variation of specificcharge
Answer» what is a relativistic charged particle ?Explain the variation of specificcharge

Discussion

1863.	A beam of light is converging towards a point I on a screen. A plane glass plate whose thickness in the direction of the beam = t, refractive index = μ,is introduced in the path of the beam. The convergence point is shifted by
Answer» A beam of light is converging towards a point I on a screen. A plane glass plate whose thickness in the direction of the beam = t, refractive index = $μ$ ,is introduced in the path of the beam. The convergence point is shifted by

Discussion

1864.	Fill in the blanks with the proper words.a. The wavelength of visible light is between ........ and ........ .b. GMRT is used for ....... waves.c. A certain X-ray telescope is named after scientist .......... .d. The first scientist to use a telescope for space observation was ................... .e. The biggest optical telescope in India is situated at ......... .
Answer» Fill in the blanks with the proper words. a. The wavelength of visible light is between ........ and ........ . b. GMRT is used for ....... waves. c. A certain X-ray telescope is named after scientist .......... . d. The first scientist to use a telescope for space observation was ................... . e. The biggest optical telescope in India is situated at ......... .

Discussion

1865.	Where will these parallel rays meet/appear to meet after refraction from concave lens?
Answer» Where will these parallel rays meet/appear to meet after refraction from concave lens?

Discussion

1866.	A body of mass m starts from rest, and attains a final velocity of v m s−1 in a duration of t, with uniform acceleration. If the net force acting on the bus is given by F, then:
Answer» A body of mass $m$ starts from rest, and attains a final velocity of ${v m s}^{- 1}$ in a duration of $t$ , with uniform acceleration. If the net force acting on the bus is given by $F$ , then:

Discussion

1867.	The position of hand shown in the figure corresponds to one of the Fleming's rules.(a) Which Fleming's rule is illustrated by this hand?(b) In this figure of hand, what is indicated: (i) by the direction of forefinger? (ii) by the direction of center finger? (iii) by the direction of thumb?
Answer» The position of hand shown in the figure corresponds to one of the Fleming's rules. (a) Which Fleming's rule is illustrated by this hand? (b) In this figure of hand, what is indicated: (i) by the direction of forefinger? (ii) by the direction of center finger? (iii) by the direction of thumb?

Discussion

1868.	Q 9/90 Choose the correct statement amongfollowing. aIt is necessary that a more precisevalue is also more accurate. b It is not necessary that a moreprecise value is more accurate too. c Accuracy tells us to what resolutionor limit, the quantity is measured. d Both (2) & (3)
Answer» Q 9/90 Choose the correct statement amongfollowing. aIt is necessary that a more precisevalue is also more accurate. b It is not necessary that a moreprecise value is more accurate too. c Accuracy tells us to what resolutionor limit, the quantity is measured. d Both (2) & (3)

Discussion

1869.	A \log of wood floats in water with 1/5 of its volume above the surface. what is density of wood
Answer» A \log of wood floats in water with 1/5 of its volume above the surface. what is density of wood

Discussion

1870.	In a sonar, ultrasonic waves are sent into the sea water and the reflected waves from a sunken ship are received after 2.0 s. If the velocity of waves in sea water is 1450 ms−1, find the depth of sunken ship.
Answer» In a sonar, ultrasonic waves are sent into the sea water and the reflected waves from a sunken ship are received after $2.0 s$ . If the velocity of waves in sea water is $1450 m s - 1$ , find the depth of sunken ship.

Discussion

1871.	Two rods, one of aluminium and the other made of steel, having initial length L1 and L2 are connected together to form a single rod of length L1+L2. The coefficient of linear expansion for aluminium and steel are αa and αs respectively. If the length of each rod increases by the same amount when their temperatures are raised by ΔT ∘C, then find the value of L1L1+L2.
Answer» Two rods, one of aluminium and the other made of steel, having initial length $L_{1} and L_{2}$ are connected together to form a single rod of length $L_{1} + L_{2}$ . The coefficient of linear expansion for aluminium and steel are $α_{a} and α_{s}$ respectively. If the length of each rod increases by the same amount when their temperatures are raised by $Δ T^{\circ} C$ , then find the value of $\frac{L_{1}}{L_{1} + L_{2}}$ .

Discussion

1872.	A particle is moving in a circular path of radius r under the action of a force F if at an instant velocity of particle is v and speed of particle is increasing then 1)F.v=0 2)F.v > 0 3)F.v < 0 4)F.v >_ 0
Answer» A particle is moving in a circular path of radius r under the action of a force F if at an instant velocity of particle is v and speed of particle is increasing then 1)F.v=0 2)F.v > 0 3)F.v < 0 4)F.v >_ 0

Discussion

1873.	96.A metallic sphere of mass m falls through glycerine with terminal velocity v. If we drop a ball of mass 8M of same material into a column of glycerine the terminal velocity will be?
Answer» 96.A metallic sphere of mass m falls through glycerine with terminal velocity v. If we drop a ball of mass 8M of same material into a column of glycerine the terminal velocity will be?

Discussion

1874.	A person jumps onto a cement floor from a height of 1 m and comes to rest in 0.1 second. The same person on jumping from a height of 9 m into a sandpit, comes to rest in 1 second. Compare the forces exerted on him by cement floor and sand pit.
Answer» A person jumps onto a cement floor from a height of 1 m and comes to rest in 0.1 second. The same person on jumping from a height of 9 m into a sandpit, comes to rest in 1 second. Compare the forces exerted on him by cement floor and sand pit.

Discussion

1875.	Binding energy per nucleon versus mass number curve for nuclei is shown in the figure. W, X, Y and Z are four nuclei indicated on the curve. The process that would release energy is
Answer» Binding energy per nucleon versus mass number curve for nuclei is shown in the figure. $W, X, Y$ and $Z$ are four nuclei indicated on the curve. The process that would release energy is

Discussion

1876.	Derive g=GM/R
Answer» Derive g=GM/R

1876.

Derive g=GM/R

Answer»

Derive g=GM/R

Discussion

1877.	The flame of a gas stove is________
Answer» The flame of a gas stove is________

Discussion

1878.	A glass ball hanging from the hook of a sensitive spring balance is completely submerged in highly salty water and tap water, one by one. If the readings of spring balance when the ball is in highly salty water and tap water are x and y respectively, then :(1) x < y(2) x > y(3) x = y(4) x = 2y
Answer» A glass ball hanging from the hook of a sensitive spring balance is completely submerged in highly salty water and tap water, one by one. If the readings of spring balance when the ball is in highly salty water and tap water are x and y respectively, then : (1) x < y (2) x > y (3) x = y (4) x = 2y

Discussion

1879.	Calculate the value of average speed and average velocity respectively for a body having following as its velocity time graph
Answer» Calculate the value of average speed and average velocity respectively for a body having following as its velocity time graph

1879.

Calculate the value of average speed and average velocity respectively for a body having following as its velocity time graph

Answer»

Calculate the value of average speed and average velocity respectively for a body having following as its velocity time graph

Discussion

1880.	An object weighs 10 N in air. When immersed fully in water, it weighs only 8 N. The weight of the liquid displaced by the object will be:2
Answer» An object weighs 10 N in air. When immersed fully in water, it weighs only 8 N. The weight of the liquid displaced by the object will be: 2

Discussion

1881.	There is a change in velocity observed from 10 m/s to 15 m/s when a force of300 N is applied on a body. Calculate the mass of the body?
Answer» There is a change in velocity observed from 10 m/s to 15 m/s when a force of 300 N is applied on a body. Calculate the mass of the body?

Discussion

1882.	40. A truck pulls a mass of 1200 kilogram at constant speed of 10 metre per second on a level road the tension in coupling is 1000 Newton what is the power spent on the Mass. find tension when truck moved up Road with information 1 in 6
Answer» 40. A truck pulls a mass of 1200 kilogram at constant speed of 10 metre per second on a level road the tension in coupling is 1000 Newton what is the power spent on the Mass. find tension when truck moved up Road with information 1 in 6

Discussion

1883.	A person standing between two cliffs hitting a drum150 times in every minute. If sound of very first beatis coincide with third and forth beat, then thedistance between two cliffs is \lbrack Consider the speedof sound in air is 350 mls
Answer» A person standing between two cliffs hitting a drum150 times in every minute. If sound of very first beatis coincide with third and forth beat, then thedistance between two cliffs is \lbrack Consider the speedof sound in air is 350 mls

Discussion

1884.	Volume of a body is 40cc. The body can float in water keeping three fourth part of it under water. Find the mass and density of the body.
Answer» Volume of a body is 40cc. The body can float in water keeping three fourth part of it under water. Find the mass and density of the body.

Discussion

1885.	What is the effect of air resistance on time period, range and hieght of projectile motion?
Answer» What is the effect of air resistance on time period, range and hieght of projectile motion?

Discussion

1886.	The commercial unit of energy is : (a) watt (b) watt-hour (c) kilowatt-hour (d) kilowatt
Answer» The commercial unit of energy is : (a) watt (b) watt-hour (c) kilowatt-hour (d) kilowatt

1886.

The commercial unit of energy is : (a) watt (b) watt-hour (c) kilowatt-hour (d) kilowatt

Answer»

The commercial unit of energy is :

(a) watt

(b) watt-hour

(c) kilowatt-hour

(d) kilowatt

Discussion

1887.	When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.
Answer» When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.

Discussion

1888.	Out of the following which is the best conductor?
Answer» Out of the following which is the best conductor?

Discussion

1889.	While measuring the length of a small rod using a vernier callipers, the difference between the observed length and the true length turned out to be 0.4 mm. When the jaws are made to touch each other, the 3rd division on the vernier scale coincides with a division on the main scale, then the least count of the callipers is:
Answer» While measuring the length of a small rod using a vernier callipers, the difference between the observed length and the true length turned out to be $0.4 m m$ . When the jaws are made to touch each other, the 3rd division on the vernier scale coincides with a division on the main scale, then the least count of the callipers is:

Discussion

1890.	Which of the following statement is true regarding the hydropower plant?
Answer» Which of the following statement is true regarding the hydropower plant?

Discussion

1891.	56. How many minimum rays must be needed to draw a ray diagram of spherical mirror? Give reasons
Answer» 56. How many minimum rays must be needed to draw a ray diagram of spherical mirror? Give reasons

Discussion

1892.	Answer the following questions.a. What is the difference between mass and weight of an object. Will the mass and weight of an object on the earth be same as their values on Mars? Why?b. What are (i) free fall, (ii) acceleration due to gravity (iii) escape velocity (iv) centripetal force ?c. Write the three laws given by Kepler. How did they help Newton to arrive at the inverse square law of gravity?d. A stone thrown vertically upwards with initial velocity u reaches a height ‘h’ before coming down. Show that the time taken to go up is same as the time taken to come down.e. If the value of g suddenly becomes twice its value, it will become two times more difficult to pull a heavy object along the floor. Why?
Answer» Answer the following questions. a. What is the difference between mass and weight of an object. Will the mass and weight of an object on the earth be same as their values on Mars? Why? b. What are (i) free fall, (ii) acceleration due to gravity (iii) escape velocity (iv) centripetal force ? c. Write the three laws given by Kepler. How did they help Newton to arrive at the inverse square law of gravity? d. A stone thrown vertically upwards with initial velocity u reaches a height ‘h’ before coming down. Show that the time taken to go up is same as the time taken to come down. e. If the value of g suddenly becomes twice its value, it will become two times more difficult to pull a heavy object along the floor. Why?

Discussion

1893.	A motorist accelerates from rest to a velocity of 90 km hr−1 in 15 seconds. What is the average acceleration of the car?
Answer» A motorist accelerates from rest to a velocity of $90 k m h r^{- 1}$ in $15$ seconds. What is the average acceleration of the car?

Discussion

1894.	Water applies upthrust on an iron ball when it is completely immersed. Now, the iron ball is taken out and heated and then again it is completely immersed into the water. Compare the upthrust in the initial and final situation.
Answer» Water applies upthrust on an iron ball when it is completely immersed. Now, the iron ball is taken out and heated and then again it is completely immersed into the water. Compare the upthrust in the initial and final situation.

1894.

Water applies upthrust on an iron ball when it is completely immersed. Now, the iron ball is taken out and heated and then again it is completely immersed into the water. Compare the upthrust in the initial and final situation.

Answer»

Water applies upthrust on an iron ball when it is completely immersed. Now, the iron ball is taken out and heated and then again it is completely immersed into the water. Compare the upthrust in the initial and final situation.

Discussion

1895.	If the bulk modulus of lead is 8000000000 N/m2 and the initial density of the lead is 11.4 g/cc,then under the pressure of 200000000 N/m2 ,the density of the lead is?
Answer» If the bulk modulus of lead is 8000000000 N/m2 and the initial density of the lead is 11.4 g/cc,then under the pressure of 200000000 N/m2 ,the density of the lead is?

Discussion

1896.	WHAT IS THE MEANING OF LAW OF CONSVERTION OF ENERGY
Answer» WHAT IS THE MEANING OF LAW OF CONSVERTION OF ENERGY

Discussion

1897.	Which of the following resources is exhaustible?
Answer» Which of the following resources is exhaustible?

Discussion

1898.	The sound of an explosion on the surface of a lake is heard by a boatman 100 m away and by a diver 100 m below the point of explosion. (i) Who would hear the sound first: boatman or diver? (ii) Give a reason for your answer in part (i). (iii) If sound takes time t to reach the boatman, how much time approximately does it take to reach the diver?
Answer» The sound of an explosion on the surface of a lake is heard by a boatman 100 m away and by a diver 100 m below the point of explosion. (i) Who would hear the sound first: boatman or diver? (ii) Give a reason for your answer in part (i). (iii) If sound takes time t to reach the boatman, how much time approximately does it take to reach the diver?

1898.

The sound of an explosion on the surface of a lake is heard by a boatman 100 m away and by a diver 100 m below the point of explosion. (i) Who would hear the sound first: boatman or diver? (ii) Give a reason for your answer in part (i). (iii) If sound takes time t to reach the boatman, how much time approximately does it take to reach the diver?

Answer»

The sound of an explosion on the surface of a lake is heard by a boatman 100 m away and by a diver 100 m below the point of explosion.

(i) Who would hear the sound first: boatman or diver?

(ii) Give a reason for your answer in part (i).

(iii) If sound takes time t to reach the boatman, how much time approximately does it take to reach the diver?

Discussion

1899.	Name the fundamental force of nature which holds the planets in their orbits around the Sun.
Answer» Name the fundamental force of nature which holds the planets in their orbits around the Sun.

Discussion

1900.	A small magnet is suspended by a silk thread from a rigid support such that the magnet can freely swing. How will it rest ? Draw a diagram to show it.
Answer» A small magnet is suspended by a silk thread from a rigid support such that the magnet can freely swing. How will it rest ? Draw a diagram to show it.

Discussion

Explore topic-wise InterviewSolutions in .

A key falls from a bridge that is 45 m above the water. It falls directly into a model boat, moving with constant velocity, that is 12 m from the point of impact when the key is released. The speed of the boat is1 ) 2m/s 2 ) 4m/s3 ) 9m/s 4 ) 48m/s

Question 62(i)The graph given below compares the sales of ice-creams of two vendors for a week.Observe the graph and answer the following question.Which vendor has sold more ice-creams on Friday?

If a car travels first 40km at speed of 20km/h and next 80km at a speed of 40km/h. What is the average speed of car for entire journey?

A swimmer crosses the river along the line making an angle 135^° with the direction of flow. Velocity of the river is 5 m/s. Swimmer takes 10 seconds to cross the river of width 100 m. The velocity of swimmer with respect to water will be

Anita was driving at a speed of 85.6 km per hour. The road had a speed limit of 55 km per hour. By how much should she reduce her speed to be within the speed limit?

Calculate the mass of a charged particle in CGS units if its charge is X coloumb and specific charge is y coulomb /g

A spring of spring constant k suspends a block of mass m, find the maximum elongation of the spring when block is released from rest.

19. A satellite is revolving around earth in a circular orbit at a uniform speed v. If gravitational force suddenlydisappears, speed of the satellite will be(1) Zero(2)V(3)2V(4) Infinity

Does the speed of an object change if the frame of reference changes?

Which of the following statements is correct about a freely falling body?1. Total energy is constant.2. Potential energy changes into kinetic energy.3. Potential energy decreases.4. Kinetic energy increases.

if we throw an object horizontally and other vertically downward direction from same height.calculat time taken ,velocity of strike on ground ,time of flight for both situations?

what is a relativistic charged particle ?Explain the variation of specificcharge

A beam of light is converging towards a point I on a screen. A plane glass plate whose thickness in the direction of the beam = t, refractive index = μ,is introduced in the path of the beam. The convergence point is shifted by

Where will these parallel rays meet/appear to meet after refraction from concave lens?

A body of mass m starts from rest, and attains a final velocity of v m s−1 in a duration of t, with uniform acceleration. If the net force acting on the bus is given by F, then:

The position of hand shown in the figure corresponds to one of the Fleming's rules.(a) Which Fleming's rule is illustrated by this hand?(b) In this figure of hand, what is indicated: (i) by the direction of forefinger? (ii) by the direction of center finger? ​(iii) by the direction of thumb?

Q 9/90 Choose the correct statement amongfollowing. aIt is necessary that a more precisevalue is also more accurate. b It is not necessary that a moreprecise value is more accurate too. c Accuracy tells us to what resolutionor limit, the quantity is measured. d Both (2) & (3)

A \log of wood floats in water with 1/5 of its volume above the surface. what is density of wood

In a sonar, ultrasonic waves are sent into the sea water and the reflected waves from a sunken ship are received after 2.0 s. If the velocity of waves in sea water is 1450 ms−1, find the depth of sunken ship.

A particle is moving in a circular path of radius r under the action of a force F if at an instant velocity of particle is v and speed of particle is increasing then 1)F.v=0 2)F.v > 0 3)F.v < 0 4)F.v >_ 0

96.A metallic sphere of mass m falls through glycerine with terminal velocity v. If we drop a ball of mass 8M of same material into a column of glycerine the terminal velocity will be?

A person jumps onto a cement floor from a height of 1 m and comes to rest in 0.1 second. The same person on jumping from a height of 9 m into a sandpit, comes to rest in 1 second. Compare the forces exerted on him by cement floor and sand pit.

Binding energy per nucleon versus mass number curve for nuclei is shown in the figure. W, X, Y and Z are four nuclei indicated on the curve. The process that would release energy is

Derive g=GM/R

The flame of a gas stove is________

A glass ball hanging from the hook of a sensitive spring balance is completely submerged in highly salty water and tap water, one by one. If the readings of spring balance when the ball is in highly salty water and tap water are x and y respectively, then :(1) x < y(2) x > y(3) x = y(4) x = 2y

Calculate the value of average speed and average velocity respectively for a body having following as its velocity time graph

An object weighs 10 N in air. When immersed fully in water, it weighs only 8 N. The weight of the liquid displaced by the object will be:2

There is a change in velocity observed from 10 m/s to 15 m/s when a force of300 N is applied on a body. Calculate the mass of the body?

40. A truck pulls a mass of 1200 kilogram at constant speed of 10 metre per second on a level road the tension in coupling is 1000 Newton what is the power spent on the Mass. find tension when truck moved up Road with information 1 in 6

A person standing between two cliffs hitting a drum150 times in every minute. If sound of very first beatis coincide with third and forth beat, then thedistance between two cliffs is \lbrack Consider the speedof sound in air is 350 mls

Volume of a body is 40cc. The body can float in water keeping three fourth part of it under water. Find the mass and density of the body.

What is the effect of air resistance on time period, range and hieght of projectile motion?

The commercial unit of energy is : (a) watt (b) watt-hour (c) kilowatt-hour (d) kilowatt

When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.

Out of the following which is the best conductor?

Which of the following statement is true regarding the hydropower plant?

56. How many minimum rays must be needed to draw a ray diagram of spherical mirror? Give reasons

A motorist accelerates from rest to a velocity of 90 km hr−1 in 15 seconds. What is the average acceleration of the car?

Water applies upthrust on an iron ball when it is completely immersed. Now, the iron ball is taken out and heated and then again it is completely immersed into the water. Compare the upthrust in the initial and final situation.

If the bulk modulus of lead is 8000000000 N/m2 and the initial density of the lead is 11.4 g/cc,then under the pressure of 200000000 N/m2 ,the density of the lead is?

WHAT IS THE MEANING OF LAW OF CONSVERTION OF ENERGY

Which of the following resources is exhaustible?

Name the fundamental force of nature which holds the planets in their orbits around the Sun.

A small magnet is suspended by a silk thread from a rigid support such that the magnet can freely swing. How will it rest ? Draw a diagram to show it.

The position of hand shown in the figure corresponds to one of the Fleming's rules.(a) Which Fleming's rule is illustrated by this hand?(b) In this figure of hand, what is indicated: (i) by the direction of forefinger? (ii) by the direction of center finger? (iii) by the direction of thumb?