Pakistan MCQs

Friction acts tangentially at a contact surface.
It may be static or kinetic.

At terminal velocity, net force is zero.
The object then moves with constant velocity.

Displacement is a vector from initial to final position.
It can be zero even when distance traveled is not zero.

Distance is a scalar and depends on the actual path.
It is always nonnegative.

Average speed uses total path length.
It does not depend on direction.

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

Vector addition replaces multiple vectors with an equivalent single vector.
Its direction and magnitude depend on the original vectors.

Perpendicular vector components form a right triangle.
The resultant magnitude is found from the sum of squared components.

One kilometre equals 1,000 metres.
Therefore 3.5 km = 3.5×1,000 = 3,500 m.

One metre equals 100 centimetres.
Therefore 250 cm ÷ 100 = 2.5 m.

Percentage uncertainty is absolute uncertainty divided by measured value times 100.
0.2/10.0×100 = 2%.

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