A lamp marked 100W, 250V is lit for 10 hours. If it operates normally and 1KWh of electrical energy costs 2k, what is the cost of lighting the lamp?
Question 1 Report
A lamp marked 100W, 250V is lit for 10 hours. If it operates normally and 1KWh of electrical energy costs 2k, what is the cost of lighting the lamp?
Answer Details
The power rating of the lamp is given as 100W, and the voltage as 250V. Using the formula, Power = Voltage × Current, we can calculate the current as:
Current = Power / Voltage = 100 / 250 = 0.4A
The energy consumed by the lamp can be calculated using the formula Energy = Power × Time, where the power is in kilowatts (kW) and the time is in hours. Converting the power to kilowatts and using the given time of 10 hours, we get:
Energy = (100 / 1000) × 10 = 1kWh
From the question, we are told that 1kWh of electrical energy costs 2k. Therefore, for 1kWh of energy consumed by the lamp, the cost is 2k. Thus, for 1kWh of energy consumed by the lamp, the cost is 2k, and for the energy consumed by the lamp (which is 1kWh), the cost is:
Cost = 1 × 2 = 2k
Therefore, the cost of lighting the lamp for 10 hours is 2k. Answer: 2k.
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