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Explain why a transformer is used in electrical power lines.

Power stations use step-down transformers to decrease the voltage of the electrical output. The power lines have a constant resistance (say, R Ohms) which means there is a power loss across the lines given b...
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Answered by Zubair M. • Physics tutor
3827 Views

Explain why the pressure exerted by a gas increases as they are heated at constant volume, with references to the kinetic theory of gases.

The kinetic theory models gas particles as points moving around with a given velocity. Heating the particles causes the transfer of heat energy, which is then used to increase the particles kinetic energy. T...
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Answered by Zubair M. • Physics tutor
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How do you use a Variable Resistor to determine values to show the relationship between I and V?

As a variable resistor's resistance can be changed, we can therefore change the current in the circuit. This will be according to Ohms Law, as a simple resistor is a Ohmic Conductor. So if we set up a circui...
KG
Answered by Kanishka G. • Physics tutor
13567 Views

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
1999 Views

Why does a body engaged in uniform circular motion do no work?

It does no work because there its displacement from the center of its circular trajectory remains constant throughout the entirety of its motion. Therefore, by definition, the work done, i.e. distance travel...
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Answered by Irtaza K. • Physics tutor
3246 Views