Momentum, Force and Energy Flashcards
1
Q
Momentum
A
p = mv
Is conserved in a closed system - this is called the principle of conservation of momentum
2
Q
Newton’s first law
A
Inertia - The momentum of a body will not change unless a force acts on it
3
Q
Newton’s second law
A
Force - Force is directly proportional to the rate of change of momentum
This means F = mv/t = ma
4
Q
Newton’s third law
A
Every force as an equal an opposite reaction
5
Q
Impulse
A
The change in momentum; I = mv-mu
Measure in Ns
6
Q
Work
A
W = Fs = 0.5mv^2 = mgh
The distance is always the displacement parallel to the force
7
Q
Power
A
P = E/t = W/t = Fs/t = Fv
8
Q
E.k and E.gp
A
E.k = 1/2mv^2 E.gp = mgh
Sum of all energy changes in a closed system = 0
