power calculations

Question 1

What is the formula for calculating power in an electrical circuit?

Answer 1

Power (P) = Voltage (V) × Current (I)

Question 2

True or False: Power is measured in watts (W).

Answer 2

True

Question 3

Fill in the blank: The unit of power is __________.

Answer 3

watts

Question 4

What is the relationship between power, voltage, and current?

Answer 4

Power is the product of voltage and current.

Question 5

If a device uses 10 volts and 2 amps, what is its power consumption?

Answer 5

20 watts

Question 6

Multiple choice: What is the power used by a circuit with a current of 3 A and a voltage of 12 V? A) 9 W B) 36 W C) 4 W D) 15 W

Answer 6

B) 36 W

Question 7

What is the formula for calculating energy in joules?

Answer 7

Energy (E) = Power (P) × Time (t)

Question 8

True or False: Energy is measured in joules (J).

Answer 8

True

Question 9

Fill in the blank: Energy is the product of __________ and __________.

Answer 9

power; time

Question 10

If a light bulb uses 60 watts of power for 2 hours, how much energy does it consume?

Answer 10

432,000 joules

Question 11

What is the power consumption of a device that operates at 240 V and draws 0.5 A?

Answer 11

120 watts

Question 12

Multiple choice: If a device uses 100 W for 3 hours, how much energy does it use? A) 300 J B) 1,080,000 J C) 10,800 J D) 1,000 J

Answer 12

B) 1,080,000 J

Question 13

What is the SI unit for measuring electrical current?

Answer 13

ampere (A)

Question 14

True or False: Increasing voltage while keeping current constant will increase power.

Answer 14

True

Question 15

Fill in the blank: The formula for power can also be expressed as __________ = __________² / __________.

Answer 15

Power; Voltage; Resistance

Question 16

What is the power dissipated in a resistor of 5 ohms with a current of 2 A flowing through it?

Answer 16

20 watts

Question 17

Multiple choice: Which of the following is NOT a unit of power? A) Watt B) Horsepower C) Joule D) Kilowatt

Answer 17

C) Joule

Question 18

What is the definition of power in physics?

Answer 18

Power is the rate at which work is done or energy is transferred.

Question 19

True or False: Power can be calculated using the formula P = I²R.

Answer 19

True

Question 20

Fill in the blank: The power of an electrical device is determined by its __________ and __________.

Answer 20

voltage; current

Question 21

If a circuit has a resistance of 10 ohms and a current of 3 A, what is the power?

Answer 21

90 watts

Question 22

Multiple choice: What happens to power if the current is doubled while voltage remains constant? A) It halves B) It doubles C) It quadruples D) It stays the same

Answer 22

C) It quadruples

Question 23

What is the power consumption of a heater rated at 1500 W?

Answer 23

1500 watts

Question 24

True or False: The formula P = IV can be rearranged to find current as I = P/V.

Answer 24

True

Question 25

Fill in the blank: A watt is equivalent to __________ joules per second.

Answer 25

one

Question 26

If a device consumes 2000 J of energy in 10 seconds, what is its power?

Answer 26

200 watts

Question 27

Multiple choice: Which of the following equations correctly represents power? A) P = V/I B) P = I/R C) P = V × I D) P = R × I

Answer 27

C) P = V × I