Momentum Flashcards
What is momentums unit
Kg m/s
What equation is used to work out momentum
Momentum = mass x velocity P= m x v
What is meant by conservation of momentum
Momentum before collision= momentum after collision
What is momentum
Momentum is a quantity possessed by masses in motion
What kind of a quantity is momentum
Momentum is a vector quantity meaning it has both magnitude and direction
How do you calculate inc in momentum
Force x time= inc in momentum
What is meant by an elastic collision and give an eg
An elastic coll. = a collision in which no KE Is lost by beig transformed into other forms if energy
Eg gas particles Colliding with conatinee
What happens when only some KE Is lost in a collision and give an eg
When a ball bounces some is transformed into sound and heat
Called partially elastic
What is an inelastic collision
When two objects collide and stick together
What is an explosion collision
When a release of energy causes things to fly apart
What car safety features are there to protect people from crashes
Air bags- inflate v fast, cushions passengers head and deflates when head impacts on it , inc collision time
Crumple zones- area at front and back of car which is designed to crumple easily, dissapating the energy of he impact, inc collision time so dec force exerted on the passenger
Seatbelts- inertia reel safety belts lock in place to keep passenger tightly pressed to seat, also slightly elaticated so inc coll. time and dec impact
How do you work out velocity
Time taken
How do you work out the force of a collision
Force = change in momentum /time taken
