Forces

Question 1

Atmospheric pressure

Answer 1

The pressure caused by the weight of the air above a surface.

Question 2

Centre of gravity

Answer 2

The point in an object where the force of gravity seems to act.

Question 3

The centre of mass

Answer 3

The point in an object where all the mass of an object seems to act.

Question 4

Compression

Answer 4

Force squashing or pushing together, which changes the shape of an object.

Question 5

Contact force

Answer 5

A force that acts when an object is in contact with a surface, air, or water.

Question 6

Deformation

Answer 6

Changing shape due to a force

Question 7

Drag force

Answer 7

The force acting on an object moving through air or water that causes it to slow down.

Question 8

Elastic limit

Answer 8

The point beyond which a spring will not return to its original length when the force is removed.

Question 9

Equilibrium

Answer 9

State of an object when opposing forces are balanced.

Question 10

Extension

Answer 10

The difference between the original length of an object and the length when you apply a force.

Question 11

Fluid

Answer 11

A substance with no fixed shape, a gas or a liquid.

Question 12

Friction

Answer 12

Force opposing motion which is caused by the interaction of surfaces moving over one another. It is called ‘drag’ if one is a fluid.

Question 13

Gas pressure

Answer 13

The force exerted by air particles when they collide with a surface.

Question 14

Hooke’s law

Answer 14

A law that says that if you double the force on an object, the extension will double (directly proportional)

Question 15

Incompressible

Answer 15

Cannot be compressed (squashed).

Question 16

Law of moments

Answer 16

An object is in equilibrium if the clockwise moments equal the anticlockwise moments

Question 17

Linear relationship

Answer 17

When two variables are graphed and show a straight line which goes through the origin, and they can be called proportional.

Question 18

Liquid pressure

Answer 18

The pressure produced by collisions of particles in a liquid.

Question 19

Lubrication

Answer 19

A substance that reduces friction between surfaces when they rub together.

Question 20

Moment

Answer 20

A measure of the ability of a force to rotate an object about a pivot.

Question 21

Newton

Answer 21

The unit that forces are measured in. (N)

Question 22

Newton meters

Answer 22

The unit of moment.

Question 23

newtons per metre squared

Answer 23

The unit of pressure (also Pascals)

Question 24

Pivot

Answer 24

The point about which a lever or see-saw balances or rotates.

Question 25

Pressure

Answer 25

The ratio of force to surface area, in N/m2, and how it causes stresses in solids.

Question 26

Reaction force

Answer 26

The support force provided by a solid surface like a floor.

Question 27

Streamlined

Answer 27

Shaped to reduce resistance to motion from air or water.

Question 28

Stress

Answer 28

The effect of a force applied to a solid, found using stress = force/area.

Question 29

Tension

Answer 29

Force extending or pulling apart.

Question 30

Upthrust

Answer 30

The upward force that a liquid or gas exerts on a body floating in it produced by the collisions of the particles in the liquid or gas

Question 31

Water resistance

Answer 31

The force on an object moving through water that causes it to slow down, also known as drag.