P8 Forces

Question 1

Scalar quantity

Answer 1

Has a magnitude only

Question 2

Vector quantity

Answer 2

Has magnitude with a direction

Question 3

How do you calculate the weight of an object?

Answer 3

Weight = mass x gravitational feild strength

Question 4

What is a Resultant force?

Answer 4

A number of forces acting on an object could be replaced by a single force that has the same effect as all of the original forces acting together. Called resultant force

Question 5

What is Newton’s Ifrst Law

Answer 5

If the forces acting on an object are equal then the resultant force will be zero. So :

• the object will stay stationary if already stationary
• the object will carry on moving at a constant velocity

Question 6

Equations for moment of a force?

Answer 6

Moment of a force = force x distance

Question 7

What is a momeng

Answer 7

A force multiplier such as a crowbar that applies a much larger turning effect to the object than you actually put in.

Question 8

What are gears?

Answer 8

Gears are like levers as they can multiply the turning force. The gears exert equal and opposite forces on each other when their edges are in contact

Question 9

How do you find the centre of mass od a symmetrical object?

Answer 9

Where the lines of symmetry meet is the centre of mass

Question 10

What are the key conditions for an object to be in equilibrium?

Answer 10

• The resultant force on the object is 0

- the forces acting on the object have no overall turning effect