Work Calculation for Electric Bulb
The question asks for the amount of work done by an electric bulb given its power rating and the time duration.
Physics Formula
Power ($P$) is defined as the rate at which work ($W$) is done, or energy is transferred, over time ($t$). The formula is:
$ P = \frac{W}{t} $
To find the work done ($W$), we can rearrange the formula:
$ W = P \times t $
Applying the Values
We are given:
- Power ($P$) = 90 W
- Time ($t$) = 10 s
Substitute these values into the rearranged formula:
$ W = 90 \text{ W} \times 10 \text{ s} $
$ W = 900 \text{ J} $
The unit of work is Joules (J).
Conclusion
Therefore, the electric bulb does 900 Joules of work in 10 seconds. This matches Option A.
Important Questions from Work, Energy, and EMF
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