Which of the following statements about specific heat of a body is/are correct?

1. It depends upon mass and shape of the body
2. It is independent of mass and shape of the body
3. It depends only upon the temperature of the body

Select the correct answer using the code given below:

• 1 only

• 2 and 3

• 1 and 3

• 2 only

62.

Which one of the following is an example of the force of gravity of the earth acting on a vibrating pendulum bob?

• Applied force

• Frictional force

• Restoring force

• Virtual force

Which one of the following statements about the refractive index of a material medium with respect to air is correct?

• It can be either positive or negative

• It can have zero value

• It is unity for all materials

• It is always greater than one

Which one of the following statements about magnetic field lines is NOT correct?

• They can emanate from a point

• They do not cross each other

• Field lines between two poles cannot be precisely straight lines at the ends

• There are no field lines within a bar magnet

Two convex lenses with power 2 dioptre are kept in contact with each other. The focal length of the combined lens system is:

• 0.10 m

• 2 m

• 4 m

• 0.25 m

Light year is a unit for measurement of:

• age of universe

• very small time intervals

• very high temperature

• very large distance

Which of the following statements about electromagnetic waves, sound waves and water waves is/are correct?

1. They exhibit reflection
2. They carry energy
3. They exert pressure
4. They can travel in vacuum

Select the correct answer using the code given below:

• 1, 2 and 3

• 2 and 4

• 1 and 3 only

• 1 only

Thermal capacity of a body depends on the

• mass of the body only

• mass and shape of the body only

• density of the body

• mass, shape and temperature of the body

An object moves in a circular path with a constant speed. Which one of the following statements is correct?

• The centripetal acceleration of the object is smaller for a gentle curve (i.e., curve of larger radius) than that for a sharp curve (i.e., curve of smaller radius).

• The centripetal acceleration is greater for a gentle curve than that for a sharp curve.

• The centripetal acceleration is the same for both, the gentle and sharp curves.

• The centripetal acceleration causes the object to slow-down.

The force acting on a particle of mass m moving along the x-axis is given by F(x) = Ax² - Bx. Which one of the following is the potential energy of the particle?

• 2Ax - B

• $-\frac{x^2}{6}\left(2Ax - 3B\right)$

• Ax³ - Bx²

• Zero