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Worksheet: Ohm's Law and Calculation of Resistance


A resistor is placed in a circuit with an adjustable voltage source. Measurements of the voltage across and the current through the resistor are shown in the accompanying graph. Find the resistance of the resistor.


A resistor of resistance 1.8 kΩ is connected across a battery of emf 5.0 V. What is the current through the resistor?


Currents of 0.06 A can potentially kill people by making their heart fibrillate (beat in an uncontrolled manner).

What voltage can produce 0.2 A of current through a dry human body with an average resistance of 100 kΩ?

A human body is made wet by heavy rain. The body has an average resistance of 100 Ω. What voltage can induce fibrillation in these circumstances?


An indicator light on a DVD player has a resistance of 300 Ω and the current in the light is 55.0 mA. How many volts are supplied to operate the light?


Calculate the effective resistance of a pocket calculator that has a 1.35 V battery if the current through the calculator is 0.200 mA.


A resistor is connected in series with a power supply of 35 V, producing a current in the resistor of 0.25 A. What is the resistance of the resistor?


What is the voltage supplied to a 1.44-kW-power short circuit through a 0.100- Ω resistance?


What is the current through the bulb of a flashlight that has a resistance of 5.0 Ω if the flashlight is powered by a battery with an emf of 4.5 V?