Answered

How much energy is consumed in 20 minutes by a bulb when 210mA current is passing through it when it is connected to a 50-V battery?



How much does it cost to use the bulb 90 minutes daily for two months if the price is S0.62 /kWh

Verified Answer :

MathPhys

Answer:

3.5 Wh

$11.72

Explanation:

The electrical energy consumed is equal to the power times the time (E = Pt). Power is equal to the voltage times the current (P = VI), where one Watt equals Volt times Ampere (1 W = VA). Given the voltage and the current, we can calculate the power consumed by the bulb. We can then calculate the energy consumed for a given amount of time, and the cost of that energy.

First, find the power consumed by the bulb.

Power = voltage × current

Power = (50 V) (0.21 A)

Power = 10.5 W

Now calculate the energy consumed in 20 minutes.

Energy = power × time

Energy = (10.5 W) (20 min) (1 hr / 60 min)

Energy = 3.5 Wh

Finally, calculate the cost of the energy consumed in 90 minutes daily for two months.

Cost = energy × price

Cost = (power × time) × price

Cost = (3.5 Wh) (90 min/day) (30 day/month) (2 month) (0.62 $/kWh) (1 kW / 1000 W)

Cost = $11.718

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