Physics 9702 · AS & A Level · Errors and uncertainties

Errors and uncertainties — practice question

(a)[1]

State the meaning of work done.

(b)[2]

Use the result from (a) to work out the SI base units of power.

(c)

The maximum useful output power $P$ of a car moving along a horizontal road is given by $P = v^3 b$, where $v$ is the car's maximum speed and $b$ is a constant. For the car, $P = 84\,\text{kW} \pm 5\%$ and $b = 0.56 \pm 7\%$ in SI units.

(c(i))[2]

Calculate $v$.

(c(ii))[2]

Determine the absolute uncertainty in $v$.

Worked solution & mark scheme

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