Mechanics | Relativity Answers

A ball is dropped from a height of 100m at the same time another ball is thrown verticaly upwards with a velocity of 25m/sec. Calculate when and where these ball meet?

According to third law of motion we say that "action and reaction are equal in magnitude but opposite in direction" but if we throw a ball from a building to earth it will touch the earth and go back but it will not reach to the floor of building from which we had throw the ball. Can you explain this?

A box with mass M slides down a ramp with friction coefficient u at a constant velocity. What is the acceleration of the box and the angle of the ramp?

I do not understand waves fully. Can you explain?

A man, though slowly, can bring a heavy barge on the water into motion, if he pulls by the rope tied to it. He is not able to do that with heavy body, lying on earth, even though his body noticeably less than the weight of the barge. Why?

To take a swing with a sitting person at a large angle, it is necessary to exert considerable force. Why is it possible to rock the swing to the same deflection angle by a much smaller effort?

Can a resultant of three equal magnitude forces applied at one point equal zero?

A ball travels 40m in 5.0 sec. What is its average velocity?

How will the clock with a pendulum on a metal rod change: a) if the temperature rises, b) during the ascent of the mountain, c) when moving from Toronto to Miami?

Why, when diving from the tower, does the swimmer seek to go into the water in a vertical rather than horizontal position?