Pakistan MCQs

Centripetal force is not a separate force type.
It may be supplied by tension, friction, gravity, or another force.

Use v²=u²-2gh with v=0.
0=400-20h, so h=20 m.

A particle in translational equilibrium has no acceleration.
It may be at rest or moving at constant velocity.

Newton's second law gives F=ma.
F=5×4 = 20 N.

Average velocity is a vector based on net displacement.
A round trip can have zero average velocity.

Slope gives change in displacement per unit time.
That is the definition of velocity.

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

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

The y-component is A sinθ.
10 sin30° = 10×0.5 = 5.

Vectors in the same direction add directly.
The resultant is 12+7 = 19 N.

Opposite collinear vectors subtract in magnitude.
The resultant magnitude is |12-7| = 5 N.

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