Force, Moments, Work And Power

Question 1

Force

Answer 1

Anything which causes an object to change its velocity

Question 2

Velocity

Answer 2

The speed in a given direction

Question 3

Forces are measured in

Answer 3

Newtons

Question 4

Push

Answer 4

Changes the velocity of an object

Question 5

Pull

Answer 5

Changes the velocity of an object

Question 6

Weight

Answer 6

Moves objects towards the ground

Question 7

Friction

Answer 7

Slows down moving objects

Question 8

Electric

Answer 8

Causes charged particles to move

Question 9

Magnetic

Answer 9

Causes magnetic materials to move

Question 10

To measure force we use a

Answer 10

Newton spring balance

Question 11

Forces always occur in pairs

Answer 11

For every force there is an equal and opposite force

Question 12

Friction

Answer 12

The force that prevents easy movement between two objects in contact

Question 13

High friction

Answer 13

Sand paper, car tyres and rough soled shoes

Question 14

Low friction

Answer 14

Wet soap, ice and glass

Question 15

Lubricant

Answer 15

Anything that reduces friction

Question 16

Friction advantages

Answer 16

Helps you stop, brakes on your car, removes rough surfaces (sandpaper), helps you walk, gives you grip to stop slipping, tyres wont spin while driving, keep you upright when walking, tyres don’t skid when driving (around corners), when cold you can rub your hands to get warm, hitting flint and steel you can make a spark to make a fire, putting extra grips onto shoes stops slipping you on ice, friction keeps nails in wood, and stops them falling out

Question 17

Disadvantages of friction

Answer 17

New shoes, braces cause blisters due to skin being rubbed, wear down new shoes, can get carpet burns if you slip, when driving, there is friction between the air and the car, so fuel is wasted trying to move the car, cartilage wears away at the joint and can be painful

Question 18

Force

Answer 18

Mass x acceleration

Question 19

Weight

Answer 19

Mass x (acceleration due to) gravity

Question 20

Work

Answer 20

Is done when a force moves an object. Work = Force x distance
Work and energy are measured in joules

Question 21

Power

Answer 21

The rate at which work is done. Power is measured in watts, where 1 watt = 1j/s

Question 22

Hooke’s Law

Answer 22

States that the extension of an elastic body (a spring) is directly proportional to the force applied to it

Question 23

A straight line graph

Answer 23

Tells you that two things on the graphs are proportional