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Define simple harmonic motion.

Simple harmonic motion is defined as a motion where the acceleration of the particle is proportional to but in the opposite direction to the displacement of the particle.
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Answered by Eemeli E. • Physics tutor
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Why does the equation for gravitational potential energy give a negative value if energy cannot be negative.

The equation is shown below as found in the IB Physcis Data Booklet. GPE = -G M m / r Where GPE is gravitational potential energy, G is the gravitational constant, M and m are the masses of the objects, and ...
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Answered by William L. • Physics tutor
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Tritium is a radioactive nucleide with a half life of 4500 days, determine the time for 90% of it to decay.

We know that the number of undecayed nuclei, N, is given by N=N 0 e -lambda t . From this, by setting N=N 0 /2 we know at this point that t= T 0.5 (the half life) and can show that lambda =ln(2)/T 0.5 . Henc...
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Answered by Luke C. • Physics tutor
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Could you go through the derivation of the Doppler effect for a source moving towards an observer?

(need a diagram showing situation). You know that the frequency emitted by the source is given by the velocity of the emitted source divided by the wavelength (f_s = v / wavelength). It is also known that fr...
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Answered by Martina P. • Physics tutor
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The diagram below represents a balloon just before take-off. The balloon’s basket is attached to the ground by two fixing ropes.Calculate the tension in either of the fixing ropes.

The first and most important step is to highlight all the important information that is given in the question. Sometimes, it is very easy to miss out key numbers that you might require to get to the final an...
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Answered by Nele W. • Physics tutor
11440 Views