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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
2002 Views

What is the quark composition of a proton?

UUD, 2 up quarks and 1 down quark
SK
Answered by Shivani K. • Physics tutor
2385 Views

An ice cube with a small iron ball in its centre is placed in a cup of water. 3.9 x 10-3kg of water in the cup is displaced and the volume of the ice cube is 4.0 x 10-6m3. Ice density: 1000 kg m-3 Iron density: 7800 kg m-3, what is the volume of the iron?

Firstly you need to know that the weight/mass of water displaced by the cube is equal to the weight/mass of the ice cube: 3.9 x 10 -3 kg You then need to recognise that the weight of the cube is the weight o...
AC
Answered by Adam C. • Physics tutor
10652 Views

Water flows through an electric shower at a rate of 6kg per minute. Assuming no heat is transferred to the surroundings, what power is required to heat the water by 20K as it flow through the shower?

To find the necessary power, we need to know how much water is flowing every second, and how much energy we need to heat that amount of water. Amount of water = 6kg per minute = 6/60 kg per second = 0.01 kg ...
TB
Answered by Theo B. • Physics tutor
2458 Views

Describe the workings behind the Photoelectric effect

In any metal, there are free surface electrons. For these electrons to escape from the surface of a metal, they require a specific amount of energy, called the 'Work Function'. There are many sources of this...
TR
Answered by Toby R. • Physics tutor
2408 Views