Kinetic energy is energy of motion. If the object is sitting still, then it has no kinetic energy. It doesn't matter what its mass is, or how high the shelf is.
KE = 0
a.) Relative velocity = velocity of car B - velocity of car A
= 19 - 14
= 5 m/s
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Answer:
60 J
Explanation:
Given That
Coefficient of performance, CoP = 4.2
Quantity of heat of the refrigerator, Q = 250 J
Work done by the refrigerator, W = ?
First, it should be noted that the Coefficient of Performance can be said to be, the ratio of the Heat required to the Work done by the system. Mathematically written as,
CoP = Q / W
Since we are already given the values from our question, we can plug it in as it's a pretty straightforward question
4.2 = 250 / W, making W subject of formula, we have
W = 250 / 4.2
W = 60J
Thus, the Work done by the refrigerator is 60 J
From the calculations, the final momentum of B is 8.16 m/s
<h3>What is conservation of linear momentum?</h3>
According to the principle of the conservation of linear momentum, the momentum before collision is equal to the total momentum after collision.
This implies that;
MaUa + MbUb = MaVa + MaVa
Substituting values;
(0.08 kg * 0.5 m/s) + (0.05 kg * 0 m/s) = (0.08 kg * −0.1 m/s) + (0.05 kg * v)
0.4 = -0.008 + 0.05v
v = 8.16 m/s
Learn more about more about momentum: brainly.com/question/24030570:
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