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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
6286 Views

A transformer has an input voltage of 4V, an output voltage of 8V and 50 turns on its primary coil. Assuming 100% efficiency, find the number of turns on the secondary coil.

Using Vp/Vs=Np/Ns, we can rearrange to get Ns= (VsNp)/VpSo, Ns = 8*50/4=100 turns.
JW
Answered by Joe W. • Physics tutor
3520 Views

A tractor pulls a plough 2km across a field using a constant force of 8N, what is the work done by the tractor?

Work done= F x d; where d= distance object has been moved through in same direction of force and F= resultant force. F=8 N.d=2 x 1000 m.WD = 2000 x 8 = 16000 J
LB
Answered by Lily B. • Physics tutor
3979 Views

What is the difference between current and voltage?

The current is the number of electrons flowing through the wire per second. The voltage however, is the amount of energy each individual electron is carrying as it moves through the wire.
JA
Answered by Jaafar A. • Physics tutor
2481 Views

A kettle has a 55% energy efficiency. The input energy for the kettle is 378,000 J per boil. Calculate the amount of energy dissipated in 5 boils.

Energy used for one boil = (3.78 x 10 5 / 100) x 55Energy used for one boil = 2.079 x 10 5 J Energy lost per boil = 3.78 x 10 5 -2.079 x 10 5 Energy lost per boil = 1.701 x 10 5 Energy lost per 5 boils = (1....
RA
Answered by Ryan A. • Physics tutor
4494 Views