Work, Energy and Power

Question 1

Work-energy theorem

Answer 1

The net/total work done on an object is equal to the change in the object’s kinetic energy (Wnet = ΔEk)

Question 2

Conservative force

Answer 2

a force for which the work done in moving an object between two points is independent of the path taken Eg. gravitational force, the elastic force in a spring, electrostatic forces (coulomb forces). CV

Question 3

non-conservative force

Answer 3

a force for which the work done in moving an object between two points depends on the path taken. Eg. frictional force, air resistance, tension in a chord.

Question 4

Principle of conservation of mechanical energy

Answer 4

the total mechanical energy (sum of gravitational potential energy and kinetic energy) in an isolated system remains constant

Question 5

Power

Answer 5

the rate at which work is done or energy is expended.