To solve the problem, we need to identify what physical quantity is measured in kilowatt-hours.
1. Understanding Kilowatt-Hour:
A kilowatt-hour (kWh) is a unit of energy commonly used to measure electrical energy consumption. It represents the amount of energy used when 1 kilowatt (1000 watts) of power is used for 1 hour.
2. Relation to Energy:
Since power × time = energy:
\( \text{Energy} = \text{Power} \times \text{Time} \)
A kilowatt-hour is a derived unit of energy.
3. SI Unit Equivalence:
1 kWh = \( 1000 \times 3600 \) joules = 3.6 × 106 joules
4. Elimination of Other Options:
- Potential difference is measured in volts (V)
- Current is measured in amperes (A)
- Electrical resistance is measured in ohms (Ω)
Final Answer:
The kilowatt-hour is the unit of Electrical energy.
An ideal low pass filter has frequency response given by \[ H(j\omega) = \begin{cases} 1, & |\omega| \leq 200\pi \\ 0, & \text{otherwise} \end{cases} \] Let \( h(t) \) be its time domain representation. Then h(0) = _________ (round off to the nearest integer).
Using shunt capacitors, the power factor of a 3-phase, 4 kV induction motor (drawing 390 kVA at 0.77 pf lag) is to be corrected to 0.85 pf lag. The line current of the capacitor bank, in A, is __________ (round off to one decimal place).
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