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How does an optical fibre transfer light?

To understand how an optical fibre transfers light, we must first understand the concept of 'total internal reflection'. Whenever light is refracted from one medium to another, the refractive index of the se...
AS
Answered by Akshay S. • Physics tutor
2394 Views

Ignoring air resistance, use an energy argument to find the speed of a ball when it hits the ground if it is dropped from 50m, where m is the mass of the ball.

Original energy: GPE=50 9.81 m KE=0 Final energy: GPE=0 KE=(1/2)mv 2 Therefore (1/2)mv 2 = 50 m 9.81 . The m cancels and simplifying the equation we are left with v 2 = 50 2 9.81, therefore v = 31 ms -1
ZT
Answered by Zach T. • Physics tutor
2802 Views

If f(x)= ln(x^2)-4, give f^-1(x)

For this question we would start by making f(x)=y. As we know the laws of logs, we can say that ln(x 2 )=2ln(x), therefore our equation can now be written as y= 2ln(x) - 4 . From this point, we want to make ...
ZT
Answered by Zach T. • Physics tutor
2752 Views

The lamp has an efficiency of 20%. Explain what this means.

20% efficiency means that 20% of the electrical energy going into the lamp is transfered to light, and 80% of the energy is lost/wasted.
BP
Answered by Bryce P. • Physics tutor
16022 Views

Explain how bright fringes arise in Young's double slit experiment

To answer this question, we need to think about 3 things: interference, phase and path difference In the experiment, we have monochromatic light (from a laser) going through two slits and then bright and dar...
HM
Answered by Harveer M. • Physics tutor
4628 Views