topic 3 revision

Question 1

momentum=

Answer 1

mass x velocity

Question 2

what is the law of conservation of momentum?

Answer 2

in an enclosed system the momentum before an event equals the momentum after the event

Question 3

what is the formula for conservation of momentum

Answer 3

(mass a x velocity a) = (mass b x velocity b)

Question 4

explain how the crumple zones protect passengers

Answer 4

by increases the impact time lowering the impact force

Question 5

change of momentum=

Answer 5

f = mass x change of velocity/t

Question 6

explain how seat belts protect passengers

Answer 6

by increases the impact time lowering the impact force

and it spreads out the force across the body

Question 7

explain how airbags protect passengers

Answer 7

by increases the impact time lowering the impact force

and it spreads out the force across the upper part of the body body

Question 8

explain how cushioned surfaces protect people

Answer 8

a softer surface reduces the impact time compared to a harder (sheesh) surface