A 100 Watt lightbulb uses 360000 Joules ever hour. How many lightbulbs could be powered for one hour by the energy from the Hiroshima bomb?

200 million electric light bulbs.

Explanation:

First, we must calculate the power of the electric bulb, for this, we use the following equation that relates the energy as a function of time.

where:

P = power [W] (units of watts)

E = energy = 360000 [J] (units of Joules)

t = time = 1 [h] = 3600 [s]

In 1 hour 1 electric lightbulb produces 100 [W], now we need to know the amount of energy produced by the Hiroshima bomb. A search made by the internet give us the data of 20 [GW] or [Gigawatts].

We need to remember that 1 Giga = 1 x10⁹

Energy Hiroshima explosion= 20*10⁹[W]

Amount = (20x10⁹)/100

Amount = 200 x10⁶ [bulbs]

That is, we would need an amount of 200 million electric light bulbs.

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