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Flashcards in Newton Deck (14):
1

Newtons 1st law

A body will remain at rest or continue to move in a straight line at a constant velocity unless an external force acts on it

2

Newtons 2nd law

The resultant force on an object is directly proportional to the rate of change of momentum of the object and the momentum change takes place in the same direction as the force

3

Newtons 3rd law

If object A exerts a force on object B, then object B will exert an equal and opposite force on object A

4

Equation for momentum

p=mv

5

Rate of change of momentum

Net force

6

Conservation of momentum

Assuming that no external forces act, total momentum is always conserved

7

Two equation for impulse

I=Ft
I=mv-mu

8

How is impulse related to momentum

It equals change in momentum

9

Area under a force time graph

Impulse

10

Rules for elastic collision

Momentum conserved
Kinetic energy conserved

11

Rules for inelastic collision

Momentum conserved
Kinetic energy not conserved

12

When can F=ma not be used

When objects are travelling close to the speed of light (resulting in their mass changing)

13

The essence of all car crash safety features

Increasing the time that it takes for the car and passengers to change their speed. This results in a lower force for the same impulse

14

Crumple Zone and its effects (2)

Areas at the front of the car that crumple upon impact
- Absorb some kinetic energy by deforming
- Increase the time it takes for the car to slow down which reduces the forces on the passengers