Pakistan MCQs

Percentage error is |48-50|/50×100.
The result is 2/50×100 = 4%.

The second is the SI base unit of time.
Minutes and hours are accepted non-SI units derived from it.

Move the decimal four places to the right to obtain 7.2.
Therefore the exponent is -4.

A scalar has magnitude only.
Speed has no associated direction.

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

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

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

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.

For two positive integers a and b, gcd(a,b) × lcm(a,b) = ab.
This identity links common factors and common multiples.