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Homework Statement
a 200 volts battery is connected to three resistors as shown, see attachment.
a) what is the potential drop across the 32 ohm resistor?
b) the 10 ohm resistor is immersed in 60 grams of water at 20 deg celsius. how long much current flow for the water to reach 40deg celsius. assume that there is not heat loss from the water through the walls of the container.
Homework Equations
parallel resistors 1/R = 1/R_1 + 1/R_2
series resistors R = R_1 + R_2
potential V = IR where I is current, R is resistance
QV/t = I^2R where Q is charge, t is time
The Attempt at a Solution
part a. first i found the parallel resistor circuit between the 10 and 40 ohm resistor, getting 8 ohms,
then i connected the new 8ohm resistor to the 32 ohm and got a single resistor of 40 ohms.
i tried using V =IR to solve for potential, but it didn't work
QV/t = I^2R , couldn't use that and solve for V because i didn't have time
does the problem involve a temperature coefficient of resistivity of water to solve for part b?
any help, for either part, appreciated
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