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wlad13 [49]
3 years ago
13

Electricity cost 10p how much will it cost to use a 85w laptop and a 60w lamp for an hour

Physics
1 answer:
Reil [10]3 years ago
7 0

Answer:

Explanation:

usually electricity is sold in the units of kWh, which I will ASSUME is the case here.

85 W (1 kW/1000W)(1hr)(10 p) = 0.85p

60 W (1 kW/1000W)(1hr)(10 p) = <u>0.60p</u>

together they would cost           1.45 p

which would be rounded down to 1 p

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At what distance along the z-axis is the electric field strength a maximum?
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<span>dE/dx = K*{(x^2 + R^2)^-1.5 - 3*x^2*(x^2 + R^2)^-2.5} </span>

<span>to find the maxima set this = 0, giving </span>

<span>(x^2 + R^2)^-1.5 - 3*x^2*(x^2 + R^2)^-2.5 = 0 </span>

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<span>(x^2 + R^2) - 3*x^2 = 0 </span>

<span>-2*x^2 + R^2 = 0 </span>

<span>-2*x^2 = -R^2 </span>

<span>x = (+/-)R/sqrt(2) </span>
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A+B+C+D+E+F+G+H+I+J+K+L+M+N+O+P
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