Question 1002666
In an electrical circuit, the current passing through a conductor varies inversely with the resistance. Suppose that when the current is 
20 A (amperes), the resistance is 7 ohms. What is the resistance when the current is 14 A ?
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E = I*R
I = E/R
20 = E/7 --> E = 140 volts
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R = E/I = 140/14
R = 10 ohms
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You don't have to know the voltage.
I = k/R (k is a constant)
k = I*R = 20*7 = 14*R
14R = 140
R = 10 ohms