Physics Work and Energy

A man of mass 50 kg jumps to a height of 1 m. His potential energy at the highest point is(g = 10 m/s²)

• (a) 500 J

• (b) 50 J

• (c) 5 J

• (d) 5000 J

The work done on an object does not depend upon the __________.

• (a) Force applied

• b)Displacement

• (c) Initial velocity of the object

• (d) none

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

• (a) 0°

• (b) 45°

• (c) 90°

• (d) 180°

Water stored in a dam possesses __________ energy.

• (a) electrical

• (b) no

• (c) potential

• (d) kinetic

Which one of the following is not the unit of work?

• (a) Joule

• (b) Newton metre

• (c) Watt

• (d) None

The number of joules contained in 1 kWh is

• (a) 36 × 10⁵ J

• (b) 3.6 × 10⁷ J

• (c) 36 × 10⁸ J

• (d) 3.7 × 10⁷ J

Work done by friction ____________ of the body.

• (a) increases kinetic energy

• (b) decreases kinetic energy

• (c) increases potential energy

• (d) decreases potential energy

One joule work is said to be done when _______________________.

• (a) a force of 1 N displaces a body by 1 cm

• (b) a force of 1 N displaces a body by 1 m

• (c) a force of 1 dyne displaces a body by 1 m

• (d) a force of 1 dyne displaces a body by 1 cm

SI unit of power is _______.

• (a) watt

• (b) joule

• (c) newton

• (d) metre

Potential energy of a body depends on its ________.

• (a) position

• (b) configuration

• (c) position and configuration

• (d) mass and velocity