Topic 9:Forces and their Effects

Question 1

What is an alternative name for the turning effect of a force?

Answer 1

A moment

Question 2

What is the equation used to calculate the moment of a force?

Answer 2

Moment of force = force x distance

Question 3

What distance measurement is used when calculating a moment?

Answer 3

The perpendicular distance from the pivot to the line of action of the force

Question 4

If an object is in equilibrium, what can be said about the moments acting on the object?

Answer 4

The clockwise moments are equal to the anti-clockwise moments

Question 5

How do levers make use of moments?

Answer 5

They increase the perpendicular distance of the force from the pivot, so decrease the force needed to produce the same moment

Question 6

How are levers used to decrease the force required to lift something?

Answer 6

Levers use a pivot point and the concept of moments to reduce the force, the further you are away from the pivot point, the less force you need to lift the object up

Question 7

How does lubricating levers/gears improve efficiency?

Answer 7

There is less resistance, less energy is wasted overcoming frictional forces

Question 8

What is a force?

Answer 8

A push or pull acting on an object due to an interaction with another object

Question 9

What are the two categories that all forces can be split into?

Answer 9

Contact and non-contact forces

Question 10

What are some examples of contact forces?

Answer 10

Friction, air-resistance and tension

Question 11

What are some examples of non-contact forces?

Answer 11

Gravitational, electrostatic and magnetic forces