Explanation:
1st- states that when two bodies interact, they apply forces to one another that are equal in magnitude and opposite in direction.
2nd- states that the time rate of change of the momentum of a body is equal in both magnitude and direction to the force imposed on it. (most important law)
3rd- states that when two bodies interact, they apply forces to one another that are equal in magnitude and opposite in direction. (law of action/reaction)
B) law of conservation of momentum
It states that the total momentum of a system before impact is the same as the total momentum of the system after impact.
In this case total momentum before impact:
10kg*5m/s + 5kg * 0m/s = 50 kg m/s
After Impact:
10kg*0m/s + 5kg*10m/s = 50 kg m/s
You can see the momentum before and after impact is same as 50 kg m/s
Of course we assumed that the first cart stopped after the impact, and there are no energy losses.
Answer:
2.0 m
Explanation:
Energy is conserved.
Initial KE = Final PE + Work done by friction
½ mv² = mgh + Fd
½ mv² = mgh + mgμd
½ v² = gh + gμd
½ v² − gh = gμd
d = (½ v² − gh) / (gμ)
d = (½ (7.5 m/s)² − (10 m/s²) (2.1 m)) / ((10 m/s²) (0.35))
d = 2.0 m
Answer: C
Explanation: Density= mass/volume
if dividing by same volume, need to increase mass in order to increase density.
same as 4=8/2 vs 8=16/2
increase numerator= increase in answer