Momentum = mass • velocity
M = m • v
Speed is a scalar quantity
Velocity is a vector quantity
That is truly the only difference
Ans: D
In a projectile motion, horizontal velocity is constant, while the ball is travelling at a constant vertical acceleration due to the gravity (9.81 ms-2 on Earth).
If the object is moving in a straight line with constant speed,
that's a description of " acceleration = zero ".
Zero acceleration means zero net force on the object.
NO net force is 'required' to keep an object moving in a straight line
at constant speed. In fact, if there IS any net force on the object,
then either its speed or its direction MUST change ... there's no way
to avoid it.
None of this depends on the object's mass, or on the speed or direction
of its motion.
