Here are the step-by-step solutions for the practice problems using Ohm's Law.
1. How much current is in a circuit that includes a 9-volt battery and a bulb with a resistance of 3 ohms?
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Formula: $I = V / R$
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Calculation: $9 \text{ volts} / 3 \text{ ohms} = 3$
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Answer: 3 amps
2. How much current is in a circuit that includes a 9-volt battery and a bulb with a resistance of 12 ohms?
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Formula: $I = V / R$
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Calculation: $9 \text{ volts} / 12 \text{ ohms} = 0.75$
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Answer: 0.75 amps
3. A circuit contains a 1.5 volt battery and a bulb with a resistance of 3 ohms. Calculate the current.
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Formula: $I = V / R$
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Calculation: $1.5 \text{ volts} / 3 \text{ ohms} = 0.5$
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Answer: 0.5 amps
4. A circuit contains two 1.5 volt batteries and a bulb with a resistance of 3 ohms. Calculate the current.
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Step 1 (Total Voltage): Since there are two batteries, add their voltages together: $1.5\text{V} + 1.5\text{V} = 3 \text{ volts}$.
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Step 2 (Current): Use the formula $I = V / R$.
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Calculation: $3 \text{ volts} / 3 \text{ ohms} = 1$
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Answer: 1 amp
5. What is the voltage of a circuit with 15 amps of current and toaster with 8 ohms of resistance?
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Formula: $V = I \times R$ (Voltage equals Current times Resistance)
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Calculation: $15 \text{ amps} \times 8 \text{ ohms} = 120$
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Answer: 120 volts
6. A light bulb has a resistance of 4 ohms and a current of 2 A. What is the voltage across the bulb?
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Formula: $V = I \times R$
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Calculation: $2 \text{ amps} \times 4 \text{ ohms} = 8$
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Answer: 8 volts
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Final Answer:
1. 3 amps
2. 0.75 amps
3. 0.5 amps
4. 1 amp
5. 120 volts
6. 8 volts
Parent Tip: Review the logic above to help your child master the concept of ohm s law worksheet.
