Energy and Motion Flashcards
1
Q
What are some potential sources of losses of energy?
A
- friction
- air resistance in vehicles
- sound energy
- electrical heating (NOT just heating)
- Work done lifting another object e.g. supports
2
Q
What must you bear in mind during m=o.5v^2 calculations?
A
When finding velocity, make sure to find the SQUARE ROOT!
3
Q
What does air resistance do?
A
Slows moving objects down.
Loses energy as heat.
4
Q
Why does a train travelling up a slope have to increase its power?
A
- Forces act down slope (gravitational forces, weight) -> bigger total force
- So train needs more work done
- … in same time, so needs more power
5
Q
What is the energy change when a cyclist cycles up a hill AT CONSTANT SPEED?
A
Chemical > gravitational potential