NAT MCQs

Use the Pythagorean theorem for perpendicular components.
Magnitude = √(3²+4²)=5.

The x-component is A cosθ.
10 cos60° = 10×0.5 = 5.

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

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

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.

The numbers correspond to C, A, K, and E.
Thus, the word is CAKE.

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