Top answers

What does the photoelectric effect demonstrate?

The dual nature of light. Sometimes it behaves as a particle, sometimes as a wave.
DM
Answered by Dario M. • Physics tutor
2056 Views

When light above the threshold frequency of a metal is shone on the metal, photoelectrons are emitted. If the power of the light halves, are the maximum kinetic energy of the photoelectrons and/or the number of photoelectrons altered, and if so, how?

When the power of the light is halved, there are half as many photons per unit time. Therefore, the number of photoelectrons emitted is also halved. The maximum kinetic energy of the photoelectrons depends o...
SS
Answered by Sam S. • Physics tutor
2178 Views

Describe an experiment, using a pendulum, which can be conducted to investigate g, acceleration due to gravity.

Set up a clamp stand with pendulum bob hanging from a thread attached to the top of the clamp stand. Set up a protractor where the thread is attached to the stand. Set up a fiduciary marker as a point of ref...
IS
Answered by Ilyas S. • Physics tutor
4844 Views

Is the excitation and de-excitation of an electron from the ground state (of an atom) due to the collision of another particle (e.g. electron) an elastic collision or an inelastic collision.

It is an elastic collision. This is because, when a particle collides with the electron of an atom, a discrete amount of energy is transferred from the particle to the electron. This discrete amount of energ...
AH
2937 Views

A person stands on top of a cliff and throws a ball with a speed of 20 m/s at an angle of 10 degrees from above the horizontal into the sea. What is the height of the cliff to 1 decimal place?

I would begin by instructing them to draw a diagram of the problem. This would be of a cliff, labelled height s y , with an arrow representing the ball being thrown from the top. This should be labelled with...
AC
Answered by Archie C. • Physics tutor
2520 Views