Question

8. A baseball is hit upward and travels along a parabolic arc before it strikes the se
the following statements must be true?
it strikes the ground. Which of
a.
The acceleration of the ball
decreases as the ball moves upward.
c. The acceleration of the ball is zero
m/s when the ball is at the highest
point in the arc.
d. The x-component of the velocity of
the ball is the same througout the
ball's flight
b.
The velocity of the ball is zero m/s
when the ball is at the highest point
in the arc.​

Answer 1

d. The x-component of the velocity of  the ball is the same througout the  ball's flight

Explanation:

The motion of the baseball is a projectile motion, which consists of two independent motions:  

- A uniform motion (constant velocity) along the horizontal direction  

- A uniformly accelerated motion, with constant acceleration (acceleration of gravity) in the downward direction.

From this description, we can already see that the correct statement is D: in fact, there is no force acting in the horizontal direction on the ball (if we neglect air resistance), therefore the acceleration in the x-direction is zero, therefore the x-component of the velocity is constant.

The other statements are wrong because:

a.  The acceleration of the ball  decreases as the ball moves upward. --> false because the acceleration remains the same ($g=9.8 m/s^2$ downward)

b.  The velocity of the ball is zero m/s  when the ball is at the highest point  in the arc.​ --> false because only the y-component of the ball's velocity is zero at the highest point, but the x-component is not zero

c. The acceleration of the ball is zero  m/s when the ball is at the highest  point in the arc. --> false because the  acceleration remains the same ($g=9.8 m/s^2$ downward)

Therefore the correct answer is

d. The x-component of the velocity of  the ball is the same througout the  ball's flight

Learn more about projectile motion:

brainly.com/question/8751410

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