Top answers

Name the four fundamental forces.

Gravitational, electromagnetic, weak and strong.
EH
Answered by Emily H. • Physics tutor
2330 Views

What causes or reduces resistance in a material?

Resistance can be thought of as the amount of distruption to the flow of electrons. If we look at the equation for resitivity:R=kl/A,where k is the resistivity of the material (and is dependant on the materi...
DG
Answered by Daniel G. • Physics tutor
2222 Views

Why is the refractive index of water bigger than that of air?

The refractive index is related to the perceived speed at which light is going in that medium. Water is more dense than air, ie there are more particles occupying a given space. So when light travels through...
MB
Answered by Miyabi B. • Physics tutor
11329 Views

"An inclined plane at an angle of 25 degrees to the horizontal has a pulley at its top. A 30kg block on the plane is connected to a freely hanging 20kg block by means of a cord passing over the pulley. From rest how far will the 20kg block fall in 2s?

For the 20kg block choose downward as positive and for the 30kg block choose the x axis along the incline as positive.Apply Newton's second law of motion to each block separately.The pulley is frictionless a...
JW
Answered by Joni W. • Physics tutor
5339 Views

Define light, critical and heavy damping in simple harmonic motion.

Damping reduces the amplitude of oscillation of a system over time. Critical damping reduces the amplitude of the oscillations to zero in the shortest possible time, returning the system to the equilibrium p...
OW
Answered by Oscar W. • Physics tutor
21166 Views