I already answered this quesiton. The fact is that there are only two kind of poles and since the two taped poles of the magnets labeled A and B attracts one to each other, we know that the two taped poles of the first two magnets are oppsosite.
Then, the taped pole of the third magnet has to be equal to one of the first two taped poles and opposite to the other of the first two taped poles.
That drives you to conclude (predict) that when she brings the taped end of the third magnet (magnet C) near each of the first two magntes, in one case they will attract each other and in the other case they will repele mutually.
<span>its kinetic energy is 7350kJ
</span>
Kinetic energy is given as =

Now, m = 12 gms = 0.012 kg
And, velocity = 35 kilometers/second = 35000 m/sec
Kinetic energy is given as =
![\frac{1}{2} 0.012 kg * 35000*35000 m/[tex] s^{2}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B2%7D%200.012%20kg%20%2A%2035000%2A35000%20m%2F%5Btex%5D%20s%5E%7B2%7D%20)
= 6

×1225 ×

m/
= 7350 kJ
Answer: N = Mgcos(theta)
Therefore, the Normal reaction force is equal to Mgcos(theta)
Explanation:
See attached for a sketch.
From the attachment.
.
N = normal reaction force on block
W = weight of the block
theta = angle of the inclined plane to the horizontal
From the sketch, we can see that
N is equal in magnitude but opposite direction to Wy
N = Wy
And
Wy = Wcos(theta)
Wx = Wsin(theta)
Then,
N = Wy = Wcos(theta)
But W = mass × acceleration due to gravity = mg
N = Mgcos(theta)
Therefore, the Normal reaction force is equal to Mgcos(theta)
Answer:
B. Make the work you do feel easier