Question

When you throw a ball horizontally, the vertical component of the ball’s speed ...

• A. continuously increases.

• B. remains zero.

• C. continuously decreases.

• D. first decreases and then increases.

• E. remains constant

When you throw a ball horizontally, the horizontal component of the ball’s speed ...

• A. remains constant.

• B. remains zero.

• C. continuously increases.

• D. continuously decreases.

• E. first decreases and then increases.

I know the answers are both A, but can someone explain why??

Answer 1

Projectile motion can be split into two: - Motion in Vertical Direction and Motion in Horizontal Direction.

When you throw a ball horizontally, initial vertical velocity is Zero

Due to gravity, there is a constant vertical acceleration in downward direction (g =9.81 m/s² ). so every 1 sec vertical velocity changes by 9.81 m/s.

if the motion is downwards vertical velocity increases .

if the motion is upwards vertical velocity decreases , ,cause g is always acting downwards .

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When you throw a ball horizontally, the horizontal component of the ball’s speed remains constant.

Because there is no acceleration in horizontal direction. if there is no acceleration then speed remains constant.