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Explain, in terms of the behaviour of molecules, how a gas exerts a pressure on the walls of its container. (4)

This question is 4 marks so you need to make at least 4 points. These types of questions just require memorising the 4 points: Lots of molecules collide with the walls. The molecules change momentum as they ...
JF
Answered by Jake F. • Physics tutor
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Describe the photoelectric effect and what it tells us about the properties of light .

The photoelectric effect describes the process by which surface electrons are emitted from a metal when light is shined on it. This occurs because the electrons are able to absorb the electromagnetic energy ...
LC
Answered by Lorenzo C. • Physics tutor
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A cup of tea contains 175 g of water at a temperature of 85.0 °C. Milk at a temperature of 4.5 °C is added to the tea and the temperature of the mixture becomes 74.0 °C. What is the internal energy lost by the water? What is the mass of the milk?

(a) In a question like this, you will be given that the Specific Heat Capacity of water is 4200Jkg -1 K -1 . However, commiting this to memory will be helpful. Start with the equation: E=mC(T 1 -T 0 ) Find w...
NS
Answered by Nathaniel S. • Physics tutor
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A satellite is in a stationary orbit above a planet of mass 8.9 x 10^25 kg and period of rotation 1.2 x 10^5 s. Calculate the radius of the satellite's orbit from the centre of the planet.

A body in a stationary orbit will always remain above the same point on the planet as it orbits. For a body to be in such an orbit, it must rotate around the planet in the same direction as the spin of the p...
DA
Answered by Dorian A. • Physics tutor
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Describe the photoelectric effect.

If we give a peice of gold negative charge and shine long wave, low frequency, electro-magnetic (E-M) radiation on it (for example radio waves) absolutely nothing will happen. If you start to shorten the wav...
US
Answered by Umar S. • Physics tutor
4922 Views