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Explain how and why the diffraction pattern of electrons passing through a slit depends on their momentum.

To understand this question, we have to consider the wave-particle duality of electrons. When passing through a slit, electrons exhibit a wavelike property- they diffract or spread out like a wave passing th...
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Answered by Thomas F. • Physics tutor
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Explain the change of quark character associated with the beta-plus decay and deduce the equation.

First, we can deduce the equation for beta-plus decay in terms of the nucleons. We know a positron, ß + (antilepton), is produced, so to conserve lepton number an electron neutrino, v e (lepton), must also b...
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Answered by Thomas F. • Physics tutor
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Why does an ice skater spin faster when they hold in their arms?

This phenomena is a result of the conservation of angular momentum: An isolated system's rotational intertia does not change. Angular momentum is given mathematically by L = r x p , by decreasing r , p = m v...
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Answered by George L. • Physics tutor
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Two balls of mass 3kg and 7 kg respectively move towards one another with speeds 5ms^-1 and 2ms^-1 respectively on a smooth table. If they collide and join, what velocity do they move off with?

m = 3kg ; 7kg u = 5ms^-1 ; -2ms^-1 (Taking the direction to the right as positive). momentum before = m1u1 + m2u2 = (3x5) + (7x-2) = 1 momentum after = (m1+m2)v2 = (3+7)v = 10v By the principle of conservati...
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Answered by Aimee G. • Physics tutor
3908 Views

Find the angle at which total internal refraction takes place when light is going from glass to air.

The angle at which this takes place is called the critical angle. We can apply Snell's law in this situation: n 1 sin C1 = n 2 sin (90deg) sin C = n 2 / n 1 If the second medium is air, then n 2 ~1, so sin C...
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Answered by Catherine T. • Physics tutor
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