16569 + Interview Questions in Physics

1.	Two stones lying on the surface of the earth have mass; a gravitational force will always exist between them. And it will try to pull the stones towards each other.But actually, we don’t see the stones moving towards each other, why? Statement 1: The acceleration because of gravitational force is in the range of 10−12ms2. Statement 2: Stones are lying on a flat surface, so they cannot move. Statement 3: The force of friction is much higher than the gravitational force. Statement 4: The stones are irregular in shape, so they cannot move. Select statements, which explains the reason for above question.
Answer» Two stones lying on the surface of the earth have mass; a gravitational force will always exist between them. And it will try to pull the stones towards each other.But actually, we don’t see the stones moving towards each other, why? Statement 1: The acceleration because of gravitational force is in the range of $10^{- 12}$ $\frac{m}{s^{2}}$ . Statement 2: Stones are lying on a flat surface, so they cannot move. Statement 3: The force of friction is much higher than the gravitational force. Statement 4: The stones are irregular in shape, so they cannot move. Select statements, which explains the reason for above question.

1.

Two stones lying on the surface of the earth have mass; a gravitational force will always exist between them. And it will try to pull the stones towards each other.But actually, we don’t see the stones moving towards each other, why? Statement 1: The acceleration because of gravitational force is in the range of 10−12ms2. Statement 2: Stones are lying on a flat surface, so they cannot move. Statement 3: The force of friction is much higher than the gravitational force. Statement 4: The stones are irregular in shape, so they cannot move. Select statements, which explains the reason for above question.

Answer»

Two stones lying on the surface of the earth have mass; a gravitational force will always exist between them. And it will try to pull the stones towards each other.But actually, we don’t see the stones moving towards each other, why?

Statement 1: The acceleration because of gravitational force is in the range of $10^{- 12}$ $\frac{m}{s^{2}}$ .
Statement 2: Stones are lying on a flat surface, so they cannot move.
Statement 3: The force of friction is much higher than the gravitational force.
Statement 4: The stones are irregular in shape, so they cannot move.

Select statements, which explains the reason for above question.

2.	What is equivalent resistance? Derive an expression for it.
Answer» What is equivalent resistance? Derive an expression for it.

3.	In the case of refraction of light from a rectangular glass slab, if i is the angle of incidence and e is the angle of emergence, then
Answer» In the case of refraction of light from a rectangular glass slab, if i is the angle of incidence and e is the angle of emergence, then

4.	State two ways by which the magnetic field due to a current carrying solenoid can be made stronger.
Answer» State two ways by which the magnetic field due to a current carrying solenoid can be made stronger.

5.	When will light behave as wave , particles and ray?
Answer» When will light behave as wave , particles and ray?

6.	1.What exactly do we mean by refractive index? 2.What happens if we perform the dispersion experiment under water?
Answer» 1.What exactly do we mean by refractive index? 2.What happens if we perform the dispersion experiment under water?

7.	A bulb is connected to a battery of p.d 4V and internal resistance 2.5ohm . A steady current of 0.5A flows through the circuit calculate 1 the total energy supplied by the battery in 10 minutes 2 the resistance of the bulb 3 the energy dissipated in the bulb in 10 minutes
Answer» A bulb is connected to a battery of p.d 4V and internal resistance 2.5ohm . A steady current of 0.5A flows through the circuit calculate 1 the total energy supplied by the battery in 10 minutes 2 the resistance of the bulb 3 the energy dissipated in the bulb in 10 minutes

9.	The black color conductor is carrying a current vertically upwards, and a magnet is placed next to it as shown. What should be the current in another wire (shown in green) in order to keep the magnet in place?
Answer» The black color conductor is carrying a current vertically upwards, and a magnet is placed next to it as shown. What should be the current in another wire (shown in green) in order to keep the magnet in place?

10.	How is voltage drop equal to potential difference ?
Answer» How is voltage drop equal to potential difference ?

12.	How does the resistance of a wire change when it's length is tripled?
Answer» How does the resistance of a wire change when it's length is tripled?

13.	A body of mass 10 kg is moving with a velocity 20 m s−1. If the mass of the body is doubled and its velocity is halved, find:(i) the initial kinetic energy, and (ii) the final kinetic energy.
Answer» A body of mass 10 kg is moving with a velocity 20 m $s^{- 1}$ . If the mass of the body is doubled and its velocity is halved, find:(i) the initial kinetic energy, and (ii) the final kinetic energy.

14.	Colour blind person may have:
Answer» Colour blind person may have:

17.	A bubble of 5.00 mol of helium is submerged at a certain depth in liquid water when the water (and thus the helium) undergoes a temperature increase ΔT of 20.0∘C; at constant pressure. As a result, the bubble expands. The helium is monoatomic and ideal. How much work W is done by the helium as it expands against the pressure of the surrounding water during the temperature increase? Use the first law of thermodynamics.
Answer» A bubble of 5.00 mol of helium is submerged at a certain depth in liquid water when the water (and thus the helium) undergoes a temperature increase $Δ T$ of ${20.0}^{\circ} C$ ; at constant pressure. As a result, the bubble expands. The helium is monoatomic and ideal. How much work W is done by the helium as it expands against the pressure of the surrounding water during the temperature increase? Use the first law of thermodynamics.

18.	When a beam of white light is passed through a prism, it splits to form lights of seven colours. Is it possible to recombine the lights of seven colours to obtain the white light again ? Explain your answer.
Answer» When a beam of white light is passed through a prism, it splits to form lights of seven colours. Is it possible to recombine the lights of seven colours to obtain the white light again ? Explain your answer.

19.	(a) Write Einstein's mass-energy equation. Give the meaning of each symbol which occurs in it. (b) If 25 atomic mass units (u) of a radioactive material are destroyed in a nuclear reaction, how much energy is released in MeV ?
Answer» (a) Write Einstein's mass-energy equation. Give the meaning of each symbol which occurs in it. (b) If 25 atomic mass units (u) of a radioactive material are destroyed in a nuclear reaction, how much energy is released in MeV ?

20.	What do you mean by the term infinity (bringing charge particle from infinity) in topic potential difference?
Answer» What do you mean by the term infinity (bringing charge particle from infinity) in topic potential difference?

21.	Write the expression for the moment of force about a given axis.
Answer» Write the expression for the moment of force about a given axis.

22.	A ray of light is incident normally on a plane glass slab. What will be (i) the angle of refraction, and (ii) the angle of deviation for the ray?
Answer» A ray of light is incident normally on a plane glass slab. What will be (i) the angle of refraction, and (ii) the angle of deviation for the ray?

23.	Assuming the earth to be sphere of uniform density, the acceleration due to gravity-
Answer» Assuming the earth to be sphere of uniform density, the acceleration due to gravity-

24.	Two satellites A and B go round a planet P in circular orbits having radii 4R and R respectively. If the speed of the satellite A is 3V, the speed of the satellite B will be.
Answer» Two satellites A and B go round a planet P in circular orbits having radii 4R and R respectively. If the speed of the satellite A is 3V, the speed of the satellite B will be.

25.	An object is placed at 30 cm in front of the convex lens of focal length 10 cm. Find out the image distance from lens.
Answer» An object is placed at 30 cm in front of the convex lens of focal length 10 cm. Find out the image distance from lens.

27.	According to mass-energy equivalence, energy contained in 1 g of mass is a×10b J. Find a+b.22
Answer» According to mass-energy equivalence, energy contained in 1 g of mass is $a \times 10^{b} J$ . Find $a + b$ . 22

28.	When will the universe end?
Answer» When will the universe end?

29.	The power of a lens is negative. State whether it is convex or concave ?
Answer» The power of a lens is negative. State whether it is convex or concave ?

30.	A toy train of mass 1 kg moves with a constant velocity of 8 m/s, when connected to a battery of 8 V for 4 s. What is the current in the circuit?
Answer» A toy train of mass $1 k g$ moves with a constant velocity of $8 m / s$ , when connected to a battery of $8 V$ for $4 s$ . What is the current in the circuit?

Explore topic-wise InterviewSolutions in Current Affairs.

What is equivalent resistance? Derive an expression for it.

In the case of refraction of light from a rectangular glass slab, if i is the angle of incidence and e is the angle of emergence, then

State two ways by which the magnetic field due to a current carrying solenoid can be made stronger.

When will light behave as wave , particles and ray?

1.What exactly do we mean by refractive index? 2.What happens if we perform the dispersion experiment under water?

A bulb is connected to a battery of p.d 4V and internal resistance 2.5ohm . A steady current of 0.5A flows through the circuit calculate 1 the total energy supplied by the battery in 10 minutes 2 the resistance of the bulb 3 the energy dissipated in the bulb in 10 minutes

Draw a labelled ray diagram to show how a ray of light is refracted when it passes : (a) from air into an optically denser medium. (b) from an optically denser medium into air.

The black color conductor is carrying a current vertically upwards, and a magnet is placed next to it as shown. What should be the current in another wire (shown in green) in order to keep the magnet in place?

How is voltage drop equal to potential difference ?

How does the resistance of a wire change when it's length is tripled?

A body of mass 10 kg is moving with a velocity 20 m s−1. If the mass of the body is doubled and its velocity is halved, find:(i) the initial kinetic energy, and (ii) the final kinetic energy.

Colour blind person may have:

Two waves of the same pitch have their amplitudes in the ratio 2:3. The ratio of their loudness will be:

In the white light of sun, maximum scattering by the air molecules present in the earth's atmosphere is for : (a) red colour (b) yellow colour (c) green colour (d) blue colour.

When a beam of white light is passed through a prism, it splits to form lights of seven colours. Is it possible to recombine the lights of seven colours to obtain the white light again ? Explain your answer.

(a) Write Einstein's mass-energy equation. Give the meaning of each symbol which occurs in it. (b) If 25 atomic mass units (u) of a radioactive material are destroyed in a nuclear reaction, how much energy is released in MeV ?

What do you mean by the term infinity (bringing charge particle from infinity) in topic potential difference?

Write the expression for the moment of force about a given axis.

A ray of light is incident normally on a plane glass slab. What will be (i) the angle of refraction, and (ii) the angle of deviation for the ray?

Assuming the earth to be sphere of uniform density, the acceleration due to gravity-

Two satellites A and B go round a planet P in circular orbits having radii 4R and R respectively. If the speed of the satellite A is 3V, the speed of the satellite B will be.

An object is placed at 30 cm in front of the convex lens of focal length 10 cm. Find out the image distance from lens.

Rainbows are formed due to A) Refraction, reflection and dispersion of light by raindrops.B) Reflection of light from rivers and ocean.C) Refraction and reflection of light by Clouds.D) Only the refraction of light by raindrops.

According to mass-energy equivalence, energy contained in 1 g of mass is a×10b J. Find a+b.22

When will the universe end?

The power of a lens is negative. State whether it is convex or concave ?

A toy train of mass 1 kg moves with a constant velocity of 8 m/s, when connected to a battery of 8 V for 4 s. What is the current in the circuit?

The boiling point of liquid increases with ___in pressure.

Why we need more power stations to transfer D.C. ?

The chemical behaviour of an atom depends upon

Explain why is the p.d. across the terminals of a cell is more in an open circuit and reduced in a closed circuit.

Name the defect of vision in a person a) whose near point is more than 25cm away b) whose far point is less than infinity

State the kind of lever which always has the Mechanical Advantage (MA) less than 1.

Question 114 The number of red blood cells per cubic millimeter of blood is approximately 5.5 million. If the average body contains 5 L of blood what is the total number of red cells in the body? Write the standard form. (1L=1000000 mm3)

The atomic mass of most common isotope of carbon in ground state is:

How is the mechanical advantage related to the velocity ratio for (i) an ideal machine, (ii) a practical machine?

During change of state, the temperature

What is linear and angular acceleration?

Calculate the work done to carry a charge of 3 C, if the potential difference between two points is 10 V.

Suggest a safe and efficient method for the disposal of biowastes and sewage materials. How is this method advantageous to us ?

What is the role of the split ring in an electic motor ?

Which of the following is not a fossil fuel? (a) LPG (b) Natural gas (c) Biogas (d) CNG

If 'i' is the critical angle, is the angle of its refracted ray.

__ is an example of a non-metal which conducts electricity.

Approximately for how many years will petroleum resources last?

The period of oscillation of a simple pendulum of length l suspended from the roof of a vehicle which moves without friction down an inclined plane of inclination α, is given by

Where will light rays meet? Here F1 and F2 represent primary focus and secondary focus of the lens respectively.

31.	The boiling point of liquid increases with ___in pressure.
Answer» The boiling point of liquid increases with ___in pressure.

32.	Why we need more power stations to transfer D.C. ?
Answer» Why we need more power stations to transfer D.C. ?

33.	The chemical behaviour of an atom depends upon
Answer» The chemical behaviour of an atom depends upon

34.	Explain why is the p.d. across the terminals of a cell is more in an open circuit and reduced in a closed circuit.
Answer» Explain why is the p.d. across the terminals of a cell is more in an open circuit and reduced in a closed circuit.

36.	State the kind of lever which always has the Mechanical Advantage (MA) less than 1.
Answer» State the kind of lever which always has the Mechanical Advantage (MA) less than 1.

38.	The atomic mass of most common isotope of carbon in ground state is:
Answer» The atomic mass of most common isotope of carbon in ground state is:

39.	How is the mechanical advantage related to the velocity ratio for (i) an ideal machine, (ii) a practical machine?
Answer» How is the mechanical advantage related to the velocity ratio for (i) an ideal machine, (ii) a practical machine?

40.	During change of state, the temperature
Answer» During change of state, the temperature

41.	What is linear and angular acceleration?
Answer» What is linear and angular acceleration?

42.	Calculate the work done to carry a charge of 3 C, if the potential difference between two points is 10 V.
Answer» Calculate the work done to carry a charge of 3 C, if the potential difference between two points is 10 V.