An electric heater is rated 1500 watt, electric power costs ? 2 per kilo-watt- hour then the cost of power for 10 hours running the heater is

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Q: 20 (NDA-II/2013)
An electric heater is rated 1500 watt, electric power costs ? 2 per kilo-watt- hour then the cost of power for 10 hours running the heater is

question_subject: 

Maths

question_exam: 

NDA-II

stats: 

0,2,2,2,0,1,1

keywords: 

{'electric power costs': [0, 0, 0, 1], 'electric heater': [0, 0, 0, 1], 'watt': [0, 0, 1, 5], 'heater': [0, 0, 2, 1], 'power': [24, 3, 21, 61], 'cost': [2, 1, 2, 10]}

The correct answer to this question is option 1: ?30.

To determine the cost of power for running the electric heater for 10 hours, we need to calculate the total energy consumed by the heater and then multiply it by the cost per kilo-watt hour.

The heater has a power rating of 1500 watts, which means it consumes 1500 joules of energy every second. Since there are 3600 seconds in an hour, the heater consumes 1500 watts x 3600 seconds = 5,400,000 joules in an hour.

To determine the energy consumed in 10 hours, we multiply this by 10, giving us a total of 54,000,000 joules.

Since 1 kilo-watt hour is equal to 3,600,000 joules, we can divide the total energy consumed by the heater (54,000,000 joules) by this conversion factor to get the energy consumption in kilo-watt hours, which is 54,000,000 joules / 3,600,000 joules = 15 kilo-watt hours.

Finally, we multiply the energy consumption (15 kWh) by the cost per kilo-watt hour (?2) to