Momentum and Impulse Flashcards
momentum
product of mass and velocity
what is momentum measured in?
kgm/s
is momentum scalar or vector?
vector
law of conservation of linear momentum
in absence of external forces, the total momentum just before a collision/explosion is equal to the total momentum just after the collision/explosion
what does the law of conservation of linear momentum apply to?
collisions between two objects in straight line
What are the two types of collisions?
elastic and inelastic
What happens in an elastic collisions to the objects?
objects bounce apart after collision
What happens to the momentum in elastic collisions?
conserved
What happens to the kinetic energy in elastic collisions?
conserved
What happens to the objects in inelastic collisions?
stick together
What happens to momentum in inelastic collisions?
conserved
What happens to kinetic energy in inelastic collisions?
decreases - changed into sound, heat, energy of deformation
How many objects are there in explosions?
one only
What happens to the objects in explosions?
split into two parts and travel in opposite directions in straight line
What happens to momentum in explosions?
conserved
What happens to kinetic energy in explosions?
increases at start object has no kinetic energy but changed potential energy into kinetic energy
impulse
what a force gives to an object when it acts on it
impulse equation
impulse = Ft impulse = change in momentum
describe a ball striking a wall.
force wall exerts on ball is 0 before impact rises to maximum as ball strikes wall and is deformed decreases to 0 as ball rebounds, regaining shape
graph to show ball striking a wall
what changes if the ball is hard? (time of contact and maximum force)
time of contact small maximum force large
what changes if the ball is soft? (time of contact and maximum force)
time of contact longer maximum force smaller
