Question

Any projectile always has a constant horizontal acceleration of _______.
A. 9.81 m.s^2
B. 0 m/s^2
C. -9.81 m/s^2
D. It is not constant.

Answer 1

Answer: B. $0 m/s^{2}$

Explanation:

When we talk about projectile motion, we have to deal with parabolic motion, which has two components: vertical and horizontal.

In the case of Earth, the acceleration is due gravity, which is constant and directed downwards (vertically) and have a value of $9.8 m/s^{2}$.

Now, in the case of the horizontal component, the acceleration will always be zero.

This is because we are dealing with parabolic movement, the x-component of the velocity remains the same (hence, there is no acceleration), while the y-component always change because it is affected by the acceleration due gravity that acts verticaly.