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Identify which of the following would be the most appropriate choice of fuse for a 1200W kettle operating on UK mains electricity (230V). A) 3A Fuse B) 5A Fuse C) 10A Fuse D) 13A Fuse

The answer is C) 10A Fuse.To calculate the current flowing to the kettle, you use the P=IV equation to work out that I=P/V. Putting P = 1200 and V = 230 into this equation gives I = 1200/230 = 5.217A. Theref...
JH
Answered by Jamie H. • Physics tutor
6302 Views

How does conservation of momentum work when at least one of the bodies in the problem changes mass?

The principle to use here is the principle of conservation of linear momentum, the question asks whether we have to modify this principle or use it in a different way to solve physics problems that have a bo...
HC
Answered by Helen C. • Physics tutor
2500 Views

Where does the formula for gravitational potential come from? Why the minus sign?

We know Newton's Law of Gravitation , which states that the force F between two bodies of masses M and m respectively, separated by distance R, can be given by: F = GMm/R 2 where G is the gravitational const...
KM
Answered by Kieren M. • Physics tutor
9499 Views

Compare and contrast elastic and inelastic collisions

An elastic collision is a collision where there is no loss of kinetic energy. Therefore, it can be said that, since KE is conserved, momentum is conserved. In other words the momentum and total kinetic energ...
MR
Answered by Matt R. • Physics tutor
16414 Views

Explain why increase in current results in higher temperature of the wire.

Current is a measure of the rate of change of charged electrons going through the wire. Therefore, when the current increases more electrons are passing through the wire in a unit time. Thus, their average v...
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Answered by Braian L. • Physics tutor
2509 Views