Topic 5- Work done and energy transfers Flashcards
What does it mean if a work force is said to do “work”
The force causes an object to be displaced through a distance
What is the equation used to calculate work done? give appropriate units
Work done= forces x distance
work done (joules), force(newtons), distance (metres)
What distance must be used when calculating work done?
It must be the distance that is moved along the line of action of the force
Under what circumstance is 1 joule of work done?
When a force of 1 newton causes a displacement of 1 metre
How many newton-metres are equal to 1 joule of energy?
1Nm = 1 J
What occurs when work is done against frictional forces?
A rise in temperature of the object occurs
Kinetic energy is converted to heat
Why does air resistance slow down a projectile?
-The object does work against the air resistance
-Kinetic energy is converted in to heat, slowing down the object
