7.1+ 7.2 Newton's Laws, Linear Momentum Flashcards
what is netwton’s 1st law?
a body remians at rest or constant velocity unless acted upon by a resultant force
magnitude and direction mus t stay constant
what is newton’s 3nd law?
if two bodies interact, they exert force upon each other which are equal in magnitude but opposite in direction
this only counts for interaction forces
whar is the paired force of the gravitational force of the earth on you?
the gravitational force from you on the earth
A person of weight 600N is standing still on the ground. State and explain the force exetreted by the person on the earth
- the person experiences a force of weight due to the earth’s garvitational pull on the person
- By Newton’s 3rd law, the person exerts a gravitational pull of 600N on the earth
what is the equation for momentum?
what is the principle of conservation of momentum?
total initial momentum= total final momentum
for both elastic and inelastic collsions
what is Netwon’s 2nd Law?
the rate of change of momentum of a body is equal to the resulatnt force acting upon it
what is an elastic collision?
kinetic energy is conserved
eg:
* two rubber balls collide: KE is transfered to elastic potential energy and then back to KE as the ball rebounds
the elastic the more KE transfored to potential energy and not waste
what is an inelastic collision?
kinetic energy is not conserved
eg:
* car accident: a lot of the kinetic energy does work in plastically deforming the cars
what is a totally inelastic collision?
bodies stick together
