Momentum

Question 1

what is momentum the product of?

Answer 1

mass and velocity

Question 2

which type of quantity is momentum? and what does it have?

Answer 2

• vector quantity

- magnitude and an associated direction.

Question 3

symbol and word equation for momentum:

Answer 3

p = mv
momentum = mass × velocity

Question 4

what is momentum measured in?

Answer 4

kg m/s

Question 5

what is a closed system? and which principle does it abide by?

Answer 5

• something that is not affected by external forces.

- conservation of momentum

Question 6

what is momentum conserved in?

Answer 6

collisions and explosions.

Question 7

what do you do with the resulting velocity of an object that has recoiled?

Answer 7

ensure that it is negative

Question 8

when is there a change in momentum?

Answer 8

when a resultant force acts on an object that is moving (or able to move)

Question 9

state the equation that calculates the force involved when a change in momentum happens:

Answer 9

f= mv-mu/t
force(N)= change in momentum(kg m/s)/ time(s)

Question 10

what is the change in velocity equal to?

Answer 10

change in momentum

Question 11

what can you deduce from the equation?

Answer 11

that the force involved is equal to the rate of change of momentum.

Question 12

what did newton’s third law state? and what does this mean?

Answer 12

• when objects collide, they will exert equal and opposite forces on each other all the time they are in contact.
• that the objects will each have the same size force acting for the same amount of time.

Question 13

how is the change of momentum calculated?

Answer 13

force x time

Question 14

what happens during a collision?

Answer 14

a change in momentum

Question 15

what do car safety features do? and why is this useful?

Answer 15

• change the shape of the car, which increases the time taken for the collision
• decrease the rate of change of momentum, which decreases the force of the collision on any people within the car.