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Physics

A Level

Define the work function of a metal

The minimum energy required by an electron to escape from a (metal) surface

Answered by George R. • Physics tutor

3450 Views

What is magnetism?

A force between moving charges

Answered by Andrew G. • Physics tutor

1554 Views

Explain the photo-electric effect and how the particle theory of light explains the phenomena. State the equation used to the determine the kinetic energy of a photo-electron and explain the origin of the terms used in your equation.

The photoelectric effect is the stimulated emission of electrons due to the irradiation of photons onto the surface of a metal. The increase in the frequency of the photons doesn’t lead to an increase in ...

Answered by Joseph G. • Physics tutor

1689 Views

The radius of the Earth is 6,400km and has a mass of 6x10^24kg. Calculate the minimum velocity needed by a projectile, fired from the surface of the Earth in order to escape the Earths gravity.

First we write down the relevant information given in the question. R_e = 6,400km = 6.4 x 10⁶ m, M_e= 6 x 10²⁴ kg.For the projectile to escape the Earths gravit...

Answered by Neil C. • Physics tutor

6151 Views

explain how a cyclotron produces a high energy electron

-cyclotron consists of 2 dees connected to an AC power supply. When an electron is released from a source in the centre of the cyclotron, it is initially attracted towards the positively charged dee, due ...

Answered by Toby S. • Physics tutor

1743 Views