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State what is meant by isotopes?

Isotopes are atoms with the same number of protons, but a different number of protons. Therefore, isotopes have the same atomic number but a different mass number.

An example of an isotope is carbo...

Answered by Charlie H. • Physics tutor

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Compare the advantages and disadvantages of the two methods of generating electricity (figure 1 in answer):

Figure 1 (AQA GCSE Science A Physics: Higher Tier):

The wind turbine costs £50 000 to buy and install.

The hydroelectric generator costs £20 000 to buy and install.

Answered by Charlie H. • Physics tutor

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Why does voltage increase (for a constant current) if temperature increases?

Voltage is directly proportional to resistant (V=IR) and resistance increases with temperature due to increased vibrations of the molecules inside the conductor. Therefore voltage increases as temperature...

Answered by Annie H. • Physics tutor

53443 Views

Could you please explain how does a general pulley system work and how I can solve problems associated with those?

Pulley systems allow for force transmission from one body to another or more. Intelligent pulley systems can be used to apply more force to a body of interest than that generated (by any power system or o...

Answered by Luca R. • Physics tutor

1337 Views

When catching a ball, a cricketer moves his hands for a short distance in the direction of travel of the ball as it makes contact with his hands. Explain why this technique results in less force being exerted on the cricketer's hands

As his hand moves back with the ball, the time taken to stop the ball is greater. This means that the rate of change of momentum is less (because the rate of him changing the speed of the ball is much slo...

Answered by Lisa W. • Physics tutor

8399 Views