Quantities associated with a moving vehicle include its velocity, speed, momentum and kinetic energy. Which of these quantities will always change if the vehicle changes direction?

Answer:

11) E

Speed does not necessarily change when a vehicle changes direction, as speed is a scalar quantity. So A, B and C are wrong.

Velocity is a vector quantity so when a vehicle changes direction, its velocity changes.

Momentum is a vector quantity as its equation is p = mv, it depends on velocity. If a vehicle changes direction, its velocity changes so its momentum also changes.

Kinetic energy does not change, as it is a scalar quantity. Energy does not depend on direction and is always positive. So when a vehicle changes direction, it is not necessary that its kinetic energy will also change.

Only momentum and velocity change. So E is that answer.