P5: MOMENTUM Flashcards
1
Q
What is momentum?
A
a measure of the tendency of an object to keep moving
2
Q
What is the equation that links momentum, mass and velocity?
A
momentum (kgm/s) = mass (kg) x velocity (m/s) (P = mv)
3
Q
What is the equation that links force, change in momentum and time?
A
force (N) = change in momentum (kgm/s) / time (s) (F = mv - mu/time)
4
Q
Why does a car have air bags?
A
-a car has airbags to increase the time taken for the driver’s momentum to reach 0 kgm/s
-this means that the force on the driver is reduced and there is less risk of injury
5
Q
What is the conservation of momentum?
A
in a closed system, the total momentum before an event = the total momentum after an event
