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a baseball is hit upward and travels along a parabolic arc before it strikes the ground. which one of the following statements is necessarily true?
the acceleration of the ball decreases as the ball moves upward.
the x - component of the velocity of the ball is the same throughout the balls flight.
the acceleration of the ball is zero m/s² when the ball is at the highest point in the arc.
the velocity of the ball is zero m/s when the ball is at the highest point in the arc.
the velocity of the ball is a maximum when the ball is at the highest point in the arc.

Explanation:

Step1: Analyze vertical - motion acceleration

In vertical - motion under gravity near the Earth's surface, the acceleration due to gravity \(g\approx9.8\ m/s^{2}\) is constant and acts downwards throughout the ball's flight. So, the acceleration of the ball does not decrease as it moves upward.

Step2: Analyze horizontal - motion velocity

In the absence of air - resistance (a common assumption in basic projectile motion), there is no horizontal force acting on the ball. According to Newton's first law (\(F = ma\), and \(F_x=0\)), the horizontal component of the velocity \(v_x\) remains constant throughout the ball's flight.

Step3: Analyze acceleration at the highest point

At the highest point of the parabolic arc, the vertical component of the velocity \(v_y = 0\), but the acceleration due to gravity is still acting downwards, so the acceleration of the ball is \(a=-g
eq0\ m/s^{2}\).

Step4: Analyze velocity at the highest point

At the highest point, the vertical component of the velocity is zero (\(v_y = 0\)), but the horizontal component \(v_x
eq0\), so the velocity of the ball is not zero at the highest point. Also, the velocity is not a maximum at the highest point; the speed is minimum at the highest point of the arc.

Answer:

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