A ball balanced on a vertical rod is an example of

- stable equilibrium
- unstable equilibrium
- neutral equilibrium
- perfect equilibrium

Which one of the following is the value of 1 kWh of energy converted into joules?

- 1.8 × 10
^{6}J - 3.6 × 10
^{6}J - 6.0 × 10
^{6}J - 7.2 × 10
^{6}J

Two bodies A and B having masses m and 4m respectively are moving with equal linear momentum. The ratio of kinetic energies between A and B is

- 1 : 2
- 1 : 1
- 4 : 1
- 1 : 4

Two cars A and B have masses m_{A} and m_{B} respectively, with m_{A} > m_{B}. Both the cars are moving in the same direction with equal kinetic energy. If equal braking force is applied on both, then before coming to rest

- A will cover a greater distance
- B will cover greater distance
- both will cover the same distance
- distance covered by them will depend on their respective velocities

The force acting on a particle of mass m moving along the x-axis is given by F(x) = Ax^{2} - Bx. Which one of the following is the potential energy of the particle?

- 2Ax - B
- -x
^{2}/6 (2Ax - 3B) - Ax
^{3}- Bx^{2} - Zero

A body is falling from a height h. After it has fallen a height h/2, it will possess

- only potential energy
- only kinetic energy
- half potential and half kinetic energy
- more kinetic and less potential energy

The work done on an object does not depend upon the

- displacement
- force applied
- angle between force and displacement
- initial velocity of the object

An iron sphere of mass 10 kg has the same diameter as an aluminium sphere of mass is 3.5 kg. Both spheres are dropped simultaneously from a tower. When they are 10 m above the ground, they have the same

- acceleration
- momenta
- potential energy
- kinetic energy

In case of negative work the angle between the force and displacement is

- 0°
- 45°
- 90°
- 180°

A car is accelerated on a levelled road and attains a velocity 4 times of its initial velocity. In this process the potential energy of the car

- does not change
- becomes twice to that of initial
- becomes 4 times that of initial
- becomes 16 times that of initial

When a body falls freely towards the earth, then its total energy

- increases
- decreases
- remains constant
- first increases and then decreases