Refer to Figure 21.7 and the discussion of lights dimming when a heavy
appliance comes on. (a) Given the voltage source is 120 V , the wire resistance is, and the bulb is nominally 75.0W , what power will the bulb dissipate if a total of 15.0 A passes through the wires when the motor comes on? Assume negligible change in bulb resistance. (b) What power is consumed by the motor?
(a)The power will the bulb dissipate if a total of 15.0 A passes through the wires when the motor comes on is .
(b) The power consumed by motor is 1644 W.
Electric power is the percentage of time it takes to work or generate energy and is expressed as the work W or the transmitted energy divided by the time interval t.
Calculating resistance in the bulb,
Next step is calculating current flowing through bulb when motor comes on:
Finally, power in the bulb with motor on is:
Therefore, the power will the bulb dissipate if a total of 15.0 A passes through the wires when the motor comes on is 66.8 W.
To calculate power consumed by the motor we need to calculate current going through the motor:
Next, resistance of the motor can be calculated as:
Finally, power of the motor is:
Hence, the power consumed by motor is 1644 W.
(a) What is the unknown in a potentiometer that balances when is , and balances when role="math" localid="1656393398590" is for a standard 3.000-V emf? (b) The same is placed in the same potentiometer, which now balances when is for a standard emf of 3.100-V . At what resistance will the potentiometer balance?
94% of StudySmarter users get better grades.Sign up for free