The time taken by the runner to do the work is 1.42 seconds.
Given the data in the question;
- Work done; [tex]W = 457J[/tex]
- Power; [tex]P = 321W[/tex]
- Time elapsed; [tex]t = \ ?[/tex]
Power
Power can be simply referred to as the quantity of energy transferred per unit time.
It is expressed as;
[tex]P = \frac{W}{t}[/tex]
Where W is work done and t is time elapsed.
To determine the time it took the runner to do the work, we substitute our given values into the expression above.
[tex]P = \frac{W}{t} \\\\t = \frac{W}{P} \\\\t = \frac{457J}{321W} \\\\t = \frac{457 kgm^2/s^2}{321 kgm^2/s^3}\\\\t = 1.42s[/tex]
Therefore, the time taken by the runner to do the work is 1.42 seconds.
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