Flashcards in Topic 4- Forces And Energy Deck (20):
What is the equation for work done?
Work done= force x distance
Joules= Newton’s x meters
What is the equation for power?
Power= work done/time taken
What is the equation for a moment?
Moment of a force = force x distance
Newton meters = Newton’s x metres
What does the principle of moments state?
The sum of the clockwise moments=the sum of the anti-clockwise moments
Name the 8 energy stores
What happens when a system changes?
Energy is transferred
What is the equation for efficiency?
Useful energy transferred
Define power and it’s unit
Rate of energy transfer
What happens when there is more power?
The more work it does each second
A push or pull on an object that is caused by it interacting with something
Name the two types of forces
What is Newton’s 3rd law?
Both objects feel an equal but opposite force
What does a free body force diagram show?
An isolated body and all the forces acting on it
Define resultant force
The overall force on an object or point
What do scale drawings do?
Find resultant forces
What are the 3 steps to drawing a scale drawing?
1) draw all the forces acting on an object
2) draw a line from the start of the last force to the end of the last force
3)measure the length of the resultant force on the diagram to find the magnitude of the force and the angle to find the direction
Turning effect of a force
Define a lever
Levers transfer the turning effect of a force - push one end of a lever down and the rotation around the pivot causes the other end to rise
Circular cogs with “teeth” around their edge