Question

1) A net torque always produces a(n) a) force b)angular acceleration c) linear acceleration d) centripetal acceleration

2)Internal energy is due to a) the motion of atoms. b) the potential energy associated with the relative positions of the atoms. c) both. d) neither.

3)What are the proper units for impulse? a) kg m / s2 b) kg m / s c) N s2 d) N m / s

4) The speed of a rolling object at the bottom of a hill does NOT depend upon a) its mass. b) its shape. c) the height of the hill. d) gravity.

5)Ultimately, what force causes a rolling object to slow down? a) static friction b) kinetic friction c) normal force d) gravity

6)To go from a lower orbit to a higher orbit around the Earth, you would need to a) slow down. b) speed up. c) Actually, you can’t change orbits once you’re in one.

7) Friction is essentially due to a) magnetic bonds between atoms of two surfaces. b) the absorption of heat between two surfaces. c) the release of electrons by the outer atoms of the surfaces. d) electric bonds between atoms of the two surfaces.

Answer 1

1)(b)angular acceleration

Because we know that,

torque = I alpha

2)(c)both

internal energy is due to the relative positions and intercation of the particles a metter is composed of.

3)(d)N-m/s

Impulse is:

J = m (v2 - v1)

4)(a)mass

from conservation of energy

PE = KE

1/2 m v^2 = m g h

v = sqrt (2 g h)

5)(b)Kinetic friction

Since the object is moving, kinetic frictional force acts. If its stationary then static acts

6)(b)speed up

As more energy is required

7)(b)The absorption of heat between two surfaces

energy get dissipated as heat due to frictional forces.