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State Faraday's Law of electromagnetic induction, both qualitatively and quantitatively. How is Lenz's Law included in this? (4 marks)

emf= (-) d(magnetic-flux)/dt (1 mark) Faradays law of induction states that the electromotive force induced in any closed circuit is equal to the negative rate of change of magnetic flux enclosed in the circ...
MH
Answered by Mabast H. • Physics tutor
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The mercury atoms in a fluorescent tube are excited and then emit photons in the ultraviolet region of the electromagnetic spectrum. Explain (i) how the mercury atoms become excited and (ii) how the excited atoms emit photons.

(i) As they pass through the fluorescent tube, they collide with the mercury atoms within it and this collision transfers energy to the atom. This energy transfer allows the atom's orbiting electrons to move...
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Answered by Evan H. • Physics tutor
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A light wave with wavelength 590nm shines upon a metal and causes it to emit an electron with a speed of 5x10^5 m/s. What is the work function of the metal?

The first step for this question is to find out how much energy is absorbed by the electron above its work function. This is found with the kinetic energy equation: K.E.=1/2mv^2 The mass of an electron is 9....
BJ
Answered by Bevan J. • Physics tutor
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Complete the following nuclear equation p+ -----> n + ... + ...

This is a proton decaying into a neutron and two other subatomic particles. Here you have to consider various conservation laws, including: baryon number, lepton number and charge. (Energy and momentum are a...
RS
Answered by Ryan S. • Physics tutor
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What is the angular speed of a car wheel of diameter 0.400m when the speed of the car is 108km/h?

A) 75 rad/s B) 150 rad/s C) 270 rad/s D) 540 rad/s Identify equation as w=v/r Diameter = 0.4m Radius = half the diameter = 0.2m Velocity needs to be in m/s so 108km/h = 108000m/h = 30m/s (divide by 60 twice)...
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Answered by Edward W. • Physics tutor
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