<span>d. all of the above
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All of the above definitely happens when Earth receives energy from the Sun.
Answer: Force
Explanation: Force is defined as a push or pull acting on an object
Answer:
t = 180 / 1.4 = 129 sec (time to swim horizontally across river)
S = 129 sec * V where V is speed of current and S is the distance he will be carried downstream
The problem does not specify V the speed of the river
Momentum is conserved after the collision
Momentum of 2 Kg before collision = 2 * 3 = 6
Momentum of 4 kg before collision = 4 * -3 = -12
so 6 + -12 = 2 * -4 + 4 *x where x is velocity of 4kg marble.
4x - 8 = -6
4x = 2
x = 0.5
Velocity of 4 kg marble is 0.5 m/s after collision
The 2 kg marble will move in the opposite direction to which it was moving before the collision.
by angular momentum conservation we will have
angular momentum of child + angular momentum of merry go round = 0
angular momentum of child = mvR
m = mass of child
R = radius of child
v = speed = 2 m/s
now let's say moment of inertia of merry go round is I
so we will have


so merry go round will turn in opposite direction with above speed