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A ball thrown vertically upward reachs a maximum height at 50m above the level of projection . calculate (1) the time taken to reach the height (2) the speed of the thrown at(g:10m/s^2)



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5 votes

Answer:

Time = 5.1 seconds

speed = 10 m/s

Step-by-step explanation:

Let's use the kinematic equations to solve the problem.

At the maximum height, the ball has zero velocity, so we can use the following kinematic equation:

v_f^2 = v_i^2 + 2ad

where v_f is the final velocity (which is zero), v_i is the initial velocity, a is the acceleration due to gravity (-10 m/s^2), and d is the displacement (which is 50 m).

Solving for v_i, we get:

v_i = sqrt(2ad) = sqrt(2 x (-10 m/s^2) x 50 m) = 10 m/s

Therefore, the speed of the ball when it was thrown vertically upward was 10 m/s.

To calculate the time taken to reach the maximum height, we can use the following kinematic equation:

d = v_i t + 1/2at^2

where d is the displacement (which is 50 m), v_i is the initial velocity (which is 10 m/s), a is the acceleration due to gravity (-10 m/s^2), and t is the time taken.

Solving for t, we get:

t = (-v_i ± sqrt(v_i^2 - 4ad)) / 2a

Since the ball was thrown vertically upward, we use the positive root:

t = (-10 m/s + sqrt((10 m/s)^2 - 4 x (-10 m/s^2) x 50 m)) / 2 x (-10 m/s^2) ≈ 5.1 s

Therefore, the time taken for the ball to reach the maximum height is approximately 5.1 seconds.

User Mark Chackerian
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