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What is an (electrostatically) induced charge?

When an electrically charged object (e.g rod) charges an uncharged object (e.g. metal sphere) that is nearby with the opposite charge. How does this happen? The charged rod causes the charges on the sphere t...
HT
Answered by Herminia T. • Physics tutor
23221 Views

Two electrons are a distance r apart, the first electron exerts a force F on the second electron. a) What force does the second electron exert on the first? b) In terms of r, at what distance is the force that the first electron exerts on the second F/9?

This question is on electric forces between charged particles. A useful equation to consider is Coulomb's law: F=k(Q 1 Q 2 )/R 2 Where k is the Coulomb's law constant:k~9.0x10 9 Nm 2 /C 2 Q is the charge on ...
RW
Answered by Ross W. • Physics tutor
7131 Views

A rollercoaster carriage of mass 100kg has 45kJ of Kinetic Energy at the lowest point of its ride. Ignoring air resistance and friction between the wheels and the tracks, what is the maximum height above this point it could reach? [Take g as 10m/s/s)

[A useful tip: always start by drawing a diagram!!]This question is asking you to apply conservation of energy, i.e. at the highest point it can reach above the lowest point, all of this Kinetic Energy will ...
RW
Answered by Ross W. • Physics tutor
4539 Views

How can I find out the Young's modulus of a material?

Right, so the Young's modulus of a material is a measure of it's rigidity. The higher the value of the Young's modulus, the more rigid the material is.Ok, so the Young's modulus, E, is equal to the stress th...
WS
Answered by William S. • Physics tutor
7314 Views

Two identical uniform spheres each of radius R are placed in contact. The gravitational force between them is F. They are then separated until the force between them is one ninth of the magnitude. What is the distance between the surfaces of the spheres?

With electostatics, it is important to remember that inthe equation giving the force between two point charges, the force is inversely proportional to the square of the distance of the charges. It is importa...
MS
Answered by Mrinank S. • Physics tutor
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