A ball is thrown at an angle of to the ground.If the ball lands 30 m away,what was the initial speed of the ball? Let .

Question

A ball is thrown at an angle of  to the ground.If the ball lands 30 m away,what was the initial speed of the ball? Let  .

Quizplus · Accepted Answer

We can use the kinematic equations to solve for the initial velocity of the ball. Since the angle of launch is given, we can determine the horizontal and vertical components of the initial velocity.

Let v0 be the initial velocity of the ball, then:

Horizontal component: v0x = v0cos(11°) 
Vertical component: v0y = v0sin(11°)

The time of flight, t, can be determined using the formula:

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where g is the acceleration due to gravity and h is the maximum height reached by the ball.

Since the ball lands at the same height it was launched, we know that h = 0. Thus:

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Now we can use the horizontal component of the velocity to find the distance the ball travels:

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Substituting the known values:

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Solving for v0:

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Therefore, the best choice is C.

A Ball Is Thrown at an Angle of to the Ground.If