Calculate the maximum current a 140 ohms, 1/2 watt

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To calculate the maximum current for a 140-ohm, 1/2 watt resistor, the formula P = I²R can be used, where P is power, I is current, and R is resistance. The maximum power of 0.5 watts and resistance of 140 ohms yield a maximum current of approximately 0.134 mA. For the second part, the maximum e.m.f. can be calculated using Ohm's Law (V = IR), resulting in a maximum voltage of about 18.8 volts. Understanding these fundamental equations is crucial for solving such electrical problems. Proper calculations ensure the resistor operates safely without overheating.
Bobzombie
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I have looked thought all my notes and books and can not find the formal on how to do this question. I'm slowly going out of my mind any help would be great

Calculate the maximum current a 140 ohms, 1/2 watt resistor can have flowing through it safely.
Enter answer: mA

Then the 2nd part of the question is

What is the maximum e.m.f. which may be applied to the resistor above without causing overheating?

Enter Part 2 answer: V
 
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Don't you have some fundamental equations that relate voltage (V), resistance (R), current (I), and power (W)? You'll need them.
 
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