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There is a train A. On the roof of A is another frictionless train B of mass Mb. A mass Mc hangs off the front of A and is attached to the front of B by rope and frictionless pulley. How fast should A accelerate so that B wont fall off the roof of A.

You must carefully draw a diagram. The key to this question is to find from what perspective you should view it. The easiest way is to see that B wants to accelerate due to the weight of C. This is unaffecte...
SO
Answered by Sean O. • Physics tutor
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How to remember what is Ideal Gas Law?

The trick here is similar to remembering all complicated formulas in science: Assign some meaning to all letters that make some sense, and is easier to remember. Our formula here is pV=nRT, where p-pressure,...
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Answered by Reinis R. • Physics tutor
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Describe the key difference between a scalar and a vector quantity

A scalar quantity is one that only has magnitude while a vector has magnitude and an associated direction. For example, temperature is a scalar quantity because temperature only has magnitude/ size, there is...
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Answered by Olavo M. • Physics tutor
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X-rays and gamma rays are two types of electromagnetic radiation, state two ways in which they differ from microwave radiation

microwaves come from a different region in the electromagnetic spectrum to X-rays and gamma rays, meaning that they have a different wavelength. Since wavelength and energy are related, this also means that ...
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Answered by Hannah S. • Physics tutor
12563 Views

What is the optimum angle to throw a snowball for maximum horizontal displacement? (Ignore air resistance, assume the snowball is thrown level with the ground. The angle is measured from the ground up)

Shortest answer: 45 degrees Short Answer: If the snowball is thrown at velocity v, at angle θ The vertical component is vsin(θ) The horizontal component is vcos(θ) v = u + at t = v/a (u = 0) Airtime = 2vsin(...
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Answered by James T. • Physics tutor
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