Motion Equations

Question 1

Newton’s first law

Answer 1

A body stays at rest, or if moving it continues to move with uniform velocity, until an unbalanced force makes it behave differently.

Question 2

Resultant force is

Answer 2

F=ma

Question 3

Weight is

Answer 3

Mass X acceleration due to gravity

W=mg

Question 4

Density

Answer 4

Mass divided by volume

Question 5

Centripetal force increases with

Answer 5

Increasing mass
Increasing speed
Decreasing radius

Question 6

Momentum

Answer 6

Momentum = mass X velocity

Question 7

Principle of conservation of momentum

Answer 7

Total momentum before = total momentum after collision

Question 8

Change in momentum

Answer 8

F= m(v-u) divided by t

Question 9

Seat belts

Answer 9

Prevent passenger going through the wind screen and increase the time to come to a stop, thus reducing the force.

Question 10

Crumple zones

Answer 10

Are areas at the front of the car which collapse easily and slowly. Increase time reduce force

Question 11

Air bags

Answer 11

Extra protection

Question 12

Crash barriers

Answer 12

Stop cars from going into the other motorway. They absorb some of the kinetic energy.

Question 13

Gravitational potential energy

Answer 13

Mass X g=10 X h

Question 14

KE

Answer 14

Half mass X velocity squared