Question

Which of the following statement is not correct for an object moving along a straight path in an accelerated motion?

• A. Its speed keeps changing
• B. Its velocity always changes
• C. It always goes away from the earth
• D. A force is always acting on it

Answer 1

The correct option is C It always goes away from the earth

Acceleration of an object is equal to the rate of change of velocity of the object.

$a=dv/dt$

Hence, for an accelerated motion velocity is always changing. Also, speed is equal to the magnitude of velocity for a particle moving along a straight line. Hence, its speed is also always changing.

By newton's second law of motion,

$F=ma$

$a\ne 0⟹F\ne 0$

Hence, for an accelerated motion, force is always acting on it.

A body under acceleration on a straight line may be moving towards or away from earth.

Hence, option c is wrong.