P2 Forces

Question 1

Does a scalar quantity have magnitude and direction or just magnitude?

Answer 1

just magnitude

Question 2

Are forces scalar or vector quantities?

Answer 2

vector

Question 3

What is a contact and a non-contact force?

Answer 3

Contact - force that occurs between objects that are physically touching
non-contact - force that occurs without the objects touching each other

Question 4

Name some contact forces.

Answer 4

friction, drag, tension, normal, upthrust

Question 5

Name three non-contact forces.

Answer 5

gravity, electrostatic, magnetism

Question 6

What is gravity?

Answer 6

Force of attraction between all masses

Question 7

What is mass?

Answer 7

The amount of matter that an object is made up of and is constant in all areas of the universe

Question 8

What is weight?

Answer 8

The force acting due to gravity and is dependent of the gravitational field strength of that planet.

Question 9

What is the centre of mass?

Answer 9

The weight of an object acting at a single point

Question 10

What is the equation linking weight, mass, and gravitational field strength

Answer 10

W=mg

Question 11

What do the length of the arrows in a free body diagram represent?

Answer 11

The magnitude of the force

Question 12

What is a free body diagram used for?

Answer 12

To show the different forces acting on an object

Question 13

How are vectors added in a scale vector diagram?

Answer 13

Head to tail

Question 14

Define work done

Answer 14

The force on an object over a particular distance

Question 15

What does 1 joule of work done mean for the amount of displacement.

Answer 15

1 joule = 1 newton metre

Question 16

What also takes place during work done?

Answer 16

energy transfers

Question 17

What does it mean if an object is elastically deformed?

Answer 17

It can return back to its original shape once the force is removed.

Question 18

What does it mean if an object is inelastically deformed?

Answer 18

It cannot return back to its original shape once force is removed

Question 19

Describe the relationship between extension and force

Answer 19

They’re directly proportional

Question 20

What happens to the relationship once the limit of proportionality is exeeded?

Answer 20

It is no longer linear

Question 21

What does the gradient on a force-extension graph represent?

Answer 21

The spring constant

Question 22

What is the spring constant?

Answer 22

It refers to how easy it is to stretch or compress a spring

Question 23

What type of energy is stored if any force is applied to a spring?

Answer 23

Elastic potential energy

Question 24

What is the relationship between work done and the energy stored?

Answer 24

They are equal if the limit of proportionality is not exceeded

Question 25

What is a moment?

Answer 25

The rotational force around a pivot

Question 26

What are the moments equal to in a balanced object?

Answer 26

total clockwise moment = total anticlockwise moment

Question 27

What are the purposes of levers and gears?

Answer 27

• transmit rotational effects of forces
• magnify the size of an applied force or the distancec a force moves over