work done and energy transfer

Question 1

what does it mean if a force is said to “work”

Answer 1

the force causes an object to be displaced through a distance

Question 2

what distance must be used when calculating work done?

Answer 2

it must be the distance that is moved along the line of action of the force

Question 3

what occurs when work done is against frictional forces?

Answer 3

• a rise in temp of the object occurs

- kinetic energy is converted to heat

Question 4

why does air resistance slow down a projectile?

Answer 4

• the object does work against air resistance

- kinetic energy is converted in to heat, slowing down the object.