Week 8 Momentum and Collision Flashcards
what is the momentum equation
p = mv
what is the Newton momentum in his second law
the rate of change of momentum of a body is proportional to the resultant force acting on the body and is in the direction of that force
what is the total momentum of a system of particles
product of the total mass of the system and the CoM velocity
define a collision
relatively large force acts on an object for a brief period of time
define the impulse
time integral of force
what is the impulse equation
J = integral (F dt)
what is the average force/impulse equation
Fav = J / (tf - ti)
define the principle of conservation of momentum
If no external forces act on a system of interacting objects then the total momentum of the system is conserved
how can CoM be related to the principle of conservation of momentum
the velocity of CoM is constant if mass is constant
what are the three types of collision
elastic collision
total/perfect inelastic collision
partially inelastic collision
define elastic collisions
collision where momentum and KE is conserved
define inelastic collisions
collision where momentum is conserved and KE is not conserved. The KE is converted into other energies
what is the difference between perfect and partial inelastic collisions
for perfect inelastic collisions the colliding objects stick together after the collision moving with common velocity
what is the coefficient of restitution equation
e = modulus (v1f-v2f / v1i-v2i)
what are the 3 properties of conservative forces
> work done by a conservative force is reversible
work done on moving round a closed path under influence of a conservative force is zero
work done by a conservative force is independent of the path and depends only on the starting and finishing points
