Could be that the speed of sound is 330m/s
Answer:
The net force acting on the chair is 8 newtons, and the chair moves toward the left.
Explanation:
We can better understand this problem if we analyze it through a free body diagram. This free body diagram is attached as an image.
If we make a sum of forces acting over the chair we can find -20 + 12 = -8 [N]
The minus sign indicates that the chair is moving to the left.
The weight of the box is 50x9.8 = 490 N. The force of friction is 100N. F= μΝ so coefficient = 100/490 = 0.20
Washing your hands and taking medicine
Answer is (c), the latent heat of fusion. That is by definition the heat that 1 kg of a substance must absorb to melt in the vicinity of its melting point.