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Describe and explain the photoelectric effect in terms of photons interacting with the surface of a metal.

The photoelectric effect is the emission of electrons from a metal surface when light is incident on it. When a photon (a light particle) hits the metal surface, it interacts with the metal's electrons. The ...
JL
Answered by Jaime L. • Physics tutor
4601 Views

What is the photoelectric effect and how does it provide evidence for the quantisation of electromagnetic radiation?

(Many students have an intuitive understanding of the photoelectric effect and how it demonstrates quantisation, but it is important when preparing for an exam to be able to explain this clearly and precisel...
RP
Answered by Rohit P. • Physics tutor
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A launcher 1m tall fires tennis balls with a velocity of 15m/s at an angle of 20 degrees from horizontal. Neglecting air resistance, calculate the maximum height, time of flight and distance traveled by the ball.

While conceptually simple, drawing on understanding of kinematic equations and vectors, these projectile problems require attention to the details of the problem such as accounting for the launch height and ...
AL
Answered by Andrei L. • Physics tutor
3757 Views

Why does a skydiver go through two different terminal velocities?

When the skydiver jumps out, they are instantaneously at free fall (accelerate at 9.81 m/s). After this, a drag force from the displacement of air is felt. The drag force is proportional to the velocity squa...
SS
Answered by Saajan S. • Physics tutor
11008 Views

Why do gravitational fields around point masses obey an inverse square law?

We can approach this question using the idea of flux lines. First we consider a sphere with a constant density of flux lines at its surface, as is the case for a point mass. These flux lines all point radial...
JC
Answered by James C. • Physics tutor
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