P2P8 - Energy: Forces doing work

Question 1

How do you calculate electrical work when theres a current flowing?

Answer 1

Energy =
Potential difference X Current X Time

Question 2

How do you calculate electrical energy?

Answer 2

Energy =
Power X Time

Question 3

What is power?

Answer 3

The rate of energy transfer (or work done).

Question 4

How do you calculate energy?

Answer 4

Efficiency = (useful energy output/total energy input) x 100.

Question 5

What is a moment?

Answer 5

A moment is the turning effect of a force around a fixed point.

Question 6

Whats the equation for moment?

Whats the other equation for moment?
(Levers)

Answer 6

Moment =
Force X Perpendicular distance from pivot

Moment =
Force X Distance

Question 7

What has to happen for an object to be in equilibrium?

Answer 7

Must be either stationary, or moving at a constant speed in a straight line.

Question 8

Where is a turning effect larger?

Answer 8

As far away from the pivot

Question 9

What do we use levers and gears for?

Answer 9

Transmit (send) the rotational effect of a force from one place to another.