AQA A-Level Physics 3.1 Measurements and their errors overview quiz quiz

The newton

The joule

The ampere

The watt

$\text{kg m s}^{-1}$

$\text{kg m}^2 \text{ s}^{-2}$

$\text{kg m}^2 \text{ s}^{-3}$

$\text{kg m s}^{-2}$

$10^{-6}$

$10^{-3}$

$10^{-9}$

$10^{-12}$

It is definitely correct because the units always match

Every term has the same base units

It contains no dimensionless constants of any kind

It applies only to ideal gases and not to other systems

It causes readings to scatter randomly above and below the true value

It can always be removed simply by repeating and averaging the readings

It is a consistent offset in one direction, such as a zero error

It is exactly the same thing as the uncertainty quoted in a reading

High accuracy but low precision

Both high accuracy and high precision

A random error only

High precision but low accuracy

$1\%$

$0.1\%$

$4\%$

$10\%$

$1\%$

$5\%$

$6\%$

$2.5\%$

$3\%$

$1.5\%$

$6\%$

$9\%$

$10^{0} \text{ kg}$

$10^{4} \text{ kg}$

$10^{-2} \text{ kg}$

$10^{2} \text{ kg}$

It is a quick check that can rule out an equation if the units do not balance

It proves beyond any doubt that the equation is numerically exact and fully correct

It removes systematic errors from the measured data automatically

It converts all the quantities in the equation to the same metric prefix

By using a single more expensive instrument and reading it once

By repeating the measurement many times and taking a mean

By identifying and correcting a zero error on the instrument

By converting every measured quantity into SI base units first