AKU Science Achievement MCQs

Precision describes repeatability.
Measurements can be precise without being accurate.

Accuracy describes agreement with the true or accepted value.
Systematic error can reduce accuracy.

Systematic errors often arise from calibration or method bias.
Repeated measurements do not automatically remove them.

Random errors cause scatter around a central value.
Repeated measurements and averaging can reduce their effect.

Leading zeros are not significant, but trailing zeros after a decimal are.
Thus 4, 5, and the final zero are significant.

Matter includes solids, liquids, gases, and plasma.
It is composed of atoms, molecules, or ions.

A vector has both magnitude and direction.
Acceleration describes the rate and direction of velocity change.

An element cannot be broken down chemically into simpler substances.
Each element is identified by its atomic number.

Both sides of a valid physical equation must have the same dimensions.
Dimensional analysis can reveal inconsistent formulas.

Compounds have definite formulas and characteristic properties.
Their components can be separated only by chemical means.

The newton is derived from base units as kg·m/s².
Metre, kilogram, and second are base units.

Mixture components retain much of their individual identity.
They can often be separated by physical methods.