Answer:
av=0.333m/s, U=3.3466J
b.
Explanation:
a. let 
be the mass of block A, and
be the mass of block B. The initial velocity of A,
-The initial momentum =Final momentum since there's no external net forces.
Relative velocity before and after collision have the same magnitude but opposite direction (for elastic collisions):
-Applying the conservation of momentum. The blocks have the same velocity after collision:
#Total Mechanical energy before and after the elastic collision is equal:
Hence, the maxumim energy stored is U=3.3466J, and the velocity=0.333m/s
b. Taking the end collision:
From a above, 
We plug these values in the equation:
Answer:
Action and reaction are equal in magnitude and opposite in direction but they do not balance each other because they act on different objects so they don't cancel each other out.
hope this will help you more
To develop this problem it is necessary to apply the concepts related to the Dopler effect.
The equation is defined by
Where
= Approaching velocities
= Receding velocities
c = Speed of sound
v = Emitter speed
And
Therefore using the values given we can find the velocity through,
Assuming the ratio above, we can use any f_h and f_i with the ratio 2.4 to 1
Therefore the cars goes to 145.3m/s
3.1 the only reason i know this is cause i got it wrong
It should be true: electrons low from negative toward positive to negative toward positive because opposite charges attract each other.
I hope this was correct
