Gr12 Work-energy and power

Question 1

Define the work done on an object

Answer 1

Work done on an object kan be defined as F x cos  , where F is the
magnitude of the force, x the magnitude of the displacement and  the angle between the force and the displacement.

Question 2

State the work-energy theorem

Answer 2

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

Question 3

Define a conservative force

Answer 3

It is a force for which the work done in moving an object between two points is independent of the path taken.

Question 4

Define a non-conservative force

Answer 4

It is a force for which the work done in moving an object between two points depends on the path taken.

Question 5

State the principle of conservation of mechanical energy

Answer 5

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

Question 6

Define power

Answer 6

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