Electric Power - AP Physics C Electricity and Magnetism

1. What is the power dissipated if $3 \text{ A}$ flows through $10 \text{ }\text{Ω}$?

   $90 \text{ W}$. Using $P = I^2R = 3^2 \times 10 = 90$ W.

2. Determine the power dissipated when $400 \text{ J}$ is used in $5 \text{ s}$.

   $80 \text{ W}$. Using $P = \frac{E}{t} = \frac{400}{5} = 80$ W.

3. Identify the power dissipated in a circuit with $8 \text{ V}$ and $4 \text{ A}$.

   $32 \text{ W}$. Using $P = IV = 8 \times 4 = 32$ W.

4. What is the power dissipated in a resistor with $5 \text{ A}$ current and $10 \text{ V}$ voltage?

   $50 \text{ W}$. Using $P = IV = 5 \times 10 = 50$ W.

5. Determine the power if $500 \text{ J}$ is used in $10 \text{ s}$.

   $50 \text{ W}$. Using $P = \frac{E}{t} = \frac{500}{10} = 50$ W.

6. Calculate the power dissipated in a $20 \text{ }\text{Ω}$ resistor with $4 \text{ A}$.

   $320 \text{ W}$. Using $P = I^2R = 4^2 \times 20 = 320$ W.

7. What is the power dissipated if a device uses $240 \text{ J}$ in $2 \text{ s}$?

   $120 \text{ W}$. Using $P = \frac{E}{t} = \frac{240}{2} = 120$ W.

8. What is the power if $15 \text{ V}$ is applied across a $5 \text{ }\text{Ω}$ resistor?

   $45 \text{ W}$. Using $P = \frac{V^2}{R} = \frac{15^2}{5} = 45$ W.

9. Determine the power if $400 \text{ J}$ of energy is consumed in $10 \text{ s}$.

   $40 \text{ W}$. Using $P = \frac{E}{t} = \frac{400}{10} = 40$ W.

10. Determine the power if $300 \text{ J}$ is used in $15 \text{ s}$.

    $20 \text{ W}$. Using $P = \frac{E}{t} = \frac{300}{15} = 20$ W.

11. Which formula relates power, voltage, and current in a circuit?

    $P = IV$. Basic relationship between electrical quantities.

12. What is the relationship between power, voltage, and resistance?

    $P = \frac{V^2}{R}$. Power varies with voltage squared, inversely with resistance.

13. Calculate the power used when $100 \text{ V}$ is applied across $25 \text{ }\text{Ω}$.

    $400 \text{ W}$. Using $P = \frac{V^2}{R} = \frac{100^2}{25} = 400$ W.

14. Calculate the power dissipated in a $25 \text{ }\text{Ω}$ resistor with $5 \text{ A}$.

    $625 \text{ W}$. Using $P = I^2R = 5^2 \times 25 = 625$ W.

15. Identify the formula for power in a resistive circuit using resistance and current.

    $P = I^2R$. Derived from $P = IV$ and Ohm's law $V = IR$.

16. Identify the power dissipated if $250 \text{ J}$ is used in $5 \text{ s}$.

    $50 \text{ W}$. Using $P = \frac{E}{t} = \frac{250}{5} = 50$ W.

17. What is the power if $120 \text{ V}$ is applied across $30 \text{ }\text{Ω}$ resistor?

    $480 \text{ W}$. Using $P = \frac{V^2}{R} = \frac{120^2}{30} = 480$ W.

18. What is the power dissipated in a $50 \text{ }\text{Ω}$ resistor with $3 \text{ A}$?

    $450 \text{ W}$. Using $P = I^2R = 3^2 \times 50 = 450$ W.

19. Which formula expresses power in terms of energy used and time?

    $P = \frac{E}{t}$. Fundamental definition of power as energy rate.

20. What is the power if $12 \text{ V}$ is applied across a $3 \text{ }\text{Ω}$ resistor?

    $48 \text{ W}$. Using $P = \frac{V^2}{R} = \frac{12^2}{3} = 48$ W.

21. What is the power dissipated in a circuit with $10 \text{ V}$ and $2 \text{ A}$?

    $20 \text{ W}$. Using $P = IV = 10 \times 2 = 20$ W.

22. What is the power dissipated in a circuit with $6 \text{ V}$ and $3 \text{ A}$?

    $18 \text{ W}$. Using $P = IV = 6 \times 3 = 18$ W.

23. What is the unit of electric power in the International System of Units?

    Watt (W). Standard SI unit for power across all physics.

24. State the formula for power in a resistive circuit using voltage and resistance.

    $P = \frac{V^2}{R}$. Derived from $P = IV$ and Ohm's law $I = \frac{V}{R}$.

25. What is the power dissipated in a $40 \text{ }\text{Ω}$ resistor with $2 \text{ A}$?

    $160 \text{ W}$. Using $P = I^2R = 2^2 \times 40 = 160$ W.

26. State the formula for electric power in terms of energy and time.

    $P = \frac{E}{t}$. Power is energy per unit time by definition.

27. Calculate the power when $150 \text{ V}$ is applied across $50 \text{ }\text{Ω}$.

    $450 \text{ W}$. Using $P = \frac{V^2}{R} = \frac{150^2}{50} = 450$ W.

28. What is the power if $10 \text{ V}$ is applied across a $5 \text{ }\text{Ω}$ resistor?

    $20 \text{ W}$. Using $P = \frac{V^2}{R} = \frac{10^2}{5} = 20$ W.

29. Calculate the power dissipated if $20 \text{ J}$ of energy is used in $4 \text{ s}$.

    $5 \text{ W}$. Using $P = \frac{E}{t} = \frac{20}{4} = 5$ W.

30. What is the power dissipated in a $10 \text{ }\text{Ω}$ resistor with $2 \text{ A}$ current?

    $40 \text{ W}$. Using $P = I^2R = 2^2 \times 10 = 40$ W.

31. What is the formula for electric power in terms of current and voltage?

    $P = IV$. Power equals voltage times current by definition.

32. Which quantity measures the rate at which electrical energy is converted to another form?

    Electric power. Rate of energy conversion from electrical to other forms.

33. What is the power dissipated in a $30 \text{ }\text{Ω}$ resistor with $6 \text{ A}$?

    $1080 \text{ W}$. Using $P = I^2R = 6^2 \times 30 = 1080$ W.

34. Find the power dissipated in a circuit with $15 \text{ V}$ and $3 \text{ A}$ current.

    $45 \text{ W}$. Using $P = IV = 15 \times 3 = 45$ W.

35. What is the power dissipated in a circuit with $5 \text{ V}$ and $0.5 \text{ A}$?

    $2.5 \text{ W}$. Using $P = IV = 5 \times 0.5 = 2.5$ W.

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