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In the Photoelectric Effect, what is mean by 'threshold frequency' and how does the magnitude a photons frequency effect the electron it is absorbed by?

The threshold frequency is the minimum frequency a photon can be and still just overcome the work function (Φ) of a particular material. The threshold frequency is directly proportional to the work functi...

Answered by Josh H. • Physics tutor

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By considering Newton's second law and his law of gravitation, derive an expression for gravitational field strength g in terms of its mass, m, the distance from its center of mass, r, and the gravitational constant, G.

Newton's second law of motion is F = ma and his law of gravitation is F= GMm/r^2.g is the acceleration of free fall and can be substituted for a, F = mg.We can therefore see that g = F/m and can use that ...

Answered by River M. • Physics tutor

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What's the difference between inertial and gravitational mass?

Like charges repel and different charges attract, i.e. charges feel an electromagnetic (EM) force. Electrons (fundamental particles that 'orbit' around the nuclei of atoms) carry a negati...

Answered by Yassine B. • Physics tutor

1657 Views

How and why does a geostationary satellite stay above the same point on the Earths surface?

First I think it is useful to look at the definition of a geostationary satellite to find out why it appears to stay in the same place above the earths surface. It is an object that is above the equator, ...

Answered by Tim S. • Physics tutor

1633 Views