Ohms law - Worksheet used on prac for physics (low ability) - Name ... - Free Printable

Here is the step-by-step solution to each question using Ohm’s Law:

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Ohm’s Law Recap:

> V = I × R
Where:
- V = Voltage (in volts, V)
- I = Current (in amperes, A)
- R = Resistance (in ohms, Ω)

You can rearrange the formula as needed:
- I = V / R
- R = V / I

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## Question 1:
> A 9V torch battery produces a current of 1A. What is the resistance of the torch?

✔ Given:
V = 9 V
I = 1 A

✔ Find: R

✔ Use formula:
R = V / I

✔ Plug in values:
R = 9 V / 1 A = 9 Ω

✔ Answer: 9 Ω

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## Question 2:
> A car battery can produce a current of 2A flowing through a wire when the resistance is 6Ω. What is the potential difference of the battery?

✔ Given:
I = 2 A
R = 6 Ω

✔ Find: V

✔ Use formula:
V = I × R

✔ Plug in values:
V = 2 A × 6 Ω = 12 V

✔ Answer: 12 V

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## Question 3:
> Domestic power supply is 240V. If you touch the live wires in a hair dryer when you have a resistance with the floor of 20 Ω, what current flows through your body?

✔ Given:
V = 240 V
R = 20 Ω

✔ Find: I

✔ Use formula:
I = V / R

✔ Plug in values:
I = 240 V / 20 Ω = 12 A

⚠️ Note: This is a *very dangerous* amount of current — it can be fatal. This example illustrates why electrical safety is critical!

✔ Answer: 12 A

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## Question 4:
> The relationship between voltage, current and resistance follows the formula V = I × R. If the resistance is constant and the current increases, what will happen to the voltage?
> Increase / Decrease / Stay the same

✔ Reasoning:
From V = I × R, if R is constant, then V is directly proportional to I.
That means:
→ If I increases, then V must also increase (since R doesn’t change).

✔ Answer: Increase

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## ✔ Final Answers Summary:

1. 9 Ω
2. 12 V
3. 12 A
4. Increase

Let me know if you’d like diagrams or further explanations!