Steps 1 and 2)
The variables are W = work, P = power, and t = time. In this case, W = 9514 joules and P = 347 watts.
The goal is to solve for the unknown time t.
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Step 3)
Since we want to solve for the time, and we have known W and P values, we use the equation t = W/P
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Step 4)
t = W/P
t = 9514/347
t = 27.4178674351586
t = 27.4 seconds
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Step 5)
The lawn mower ran for about 27.4 seconds. I rounded to three sig figs because this was the lower amount of sig figs when comparing 9514 and 347.
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Note: we don't use the mass at all
The energy carried by a photon is equal to
(Planck's Konstant) times (the frequency of the photon) .
Planck's konstant is 6.626 x 10⁻³⁴ m²-kg/s (rounded)
≈ 746 watts is a 1 Horsepower, because that's in the SI base unit.
One possible unit is liter, which is a basic unit in metric system. 1 liter=10 cm^3, or 0.001 m^3, so we also know that other possible units include cubic centimeters or cubic meters, which are derived units, since they are derived from basic unit, meter, representing the length, breadth, and height of the cuboid.
