Topic 4 - Forces and Energy Flashcards Preview

Physics (Paper 1: 1-3, Paper 2: 4-7) > Topic 4 - Forces and Energy > Flashcards

Flashcards in Topic 4 - Forces and Energy Deck (13):

State the different ways in which energy can be transferred

-By heating
-By radiation


Explain what happens to energy when a system changes

It is transferred. It can be transferred into or away from the system, between different objects in the system or between different types of energy stores. It can also be dissipated or wasted.


Define work done

When a force moves an object through a distance. This makes energy transfer


Formula for work done

Work done = force x distance


Define power

The rate of energy transfer


Formula for power

Power = work done / time taken


Define force

A push or a pull on an object that is caused by it interacting with something


State the difference between contact and non-contact forces

Contact involves two objects touching (e.g. friction between a car's tyre and the road). Non-contact involves objects not touching (e.g. gravitational fields interacting)


State what a free body force diagrams shows

All the forces acting on an object


Define resultant force

The overall force of a point or object


Describe how to draw a scale drawing

1. Draw all forces acting on an object to scale
2. Then draw a straight line from the start of the first force to the end of the last force - this is the resultant force
3. Measure the length of the resultant force on the diagram to find the magnitude of the force and the angle to find its direction


State how to tell if an object is in equilibrium by using forces

If the resultant force equals to 0


Formula for resultant force

highest unit of forces in one direction - forces going in the opposite direction