Flashcards in Changes In Momentum Deck (10)

Loading flashcards...

1

## what happens when a resultant force acts on an object for certain amount of time

### it causes a change in momentum

2

## what equation from newton displays how a resultant force on an object causes it to accelerate

### force = mass x acceleration

3

## what equation using force shows that acceleration is just a change in velocity over a certain period of time

###
- force = mass x change in velocity / time

- f = m(v - u) /t

4

## why does the mass x change in velocity equal a change in momentum

###
- because a force applied to an object over any time interval will change the objects velocity

- whether that through be changing the direction of the object

- or changing its 'speed' through acceleration or deceleration

5

## what is the equation which shows that mass x change in velocity equals the change in momentum

###
- force = change in momentum / time

- F = (mv - mu) / t

6

## what are units for force, change in momentum and time

###
- force = N

- change in momentum = kg m/s

- time = s

7

## using the equation for change in momentum, what does a faster change in momentum directly imply

###
- that the force causing the change must be bigger

- as when t gets smaller (time)

- the force calculated will be bigger

8

## why is it more dangerous for a car crash to happen with cars going at faster speeds than at slower speeds

###
- at faster speeds, the change in momentum from the cars crashing and the forces acting in opposite direction is much larger

- considering the cars stop instantly when they crash

- leading to a much larger force acting on the bodies of the car when using the change in momentum equation

9

## how can you relate the cars crashing at higher and slower speeds to the equation for acceleration

###
- when the fast cars with a higher velocity crash, the change in velocity would be much larger

- for a given time for the fast and slow cars

- meaning the acceleration (or accurately deceleration) is much higher

- and because of f - ma, a larger force is needed to produce a larger acceleration

- so acceleration and change in momentum are pretty much proportional

10