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A 25 micro farad is charged until the potential difference across it is 500V. Calculate the charge stored at this moment.

The formula to be used here is C = Q / V. Where C = capacitance, Q = charge and V = potential difference. First we can put in the values to get 25 * 10^-6 = Q / 500. This can be rearranged to Q = 500 * 25 * ...
CW
Answered by Cameron W. • Physics tutor
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Explain why atmospheric pressure decreases with increasing altitude. (3 marks)

Firstly, pressure is created by air molecules colliding with a surface. At an increased altitude there are fewer air molecules, and therefore a larger average distance between them. This means at this higher...
EB
Answered by Emily B. • Physics tutor
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A ball is released from height h w.r.t. the ground. Draw a qualitative height versus time diagram of the ball bouncing in a non-ideal case.

In a non-ideal case, there will be energy loss in heat when the ball touches the ground. In particular: K n =aK n-1 , where K n-1 is the kinetic energy before the nth bounce, K n is the kinetic energy after ...
EP
Answered by Emanuele P. • Physics tutor
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A car of mass M and a maximum power output of P is on an rough inclined plane Θ to the horizontal. What is the maximum velocity (v). Coefficient of friction=μ and air resistance=kv where k is constant

At the maximum velocity the driving force of the car is equal to the sum of the opposing forces: F driving =F friction +F air +mg sinΘ F friction =mgμ cosΘ F air =kv p=[mgμ cosΘ+ kv+mg sinΘ]v = [μ cosΘ+sinΘ]...
JB
Answered by Joel B. • Physics tutor
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Help! How do I rearrange equations?

Being able to manipulate equations is a very useful skill in Physics. Consider, for example, the relationship between mass, density and volume. m = ρ x v In the above equation, the mass, m is the subject bec...
IP
Answered by Ijeoma P. • Physics tutor
2556 Views