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A stone is thrown into the air in an angle. One second later it is observed to have a speed of 8 m/s15


below the horizontal. What is the initial velocity of the stone? Calculate its maximum height

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User Spike
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Answer:

We can use the kinematic equations of motion to solve this problem. Let's assume that the initial velocity of the stone is v0, and that it is thrown at an angle θ above the horizontal. We can then break down the initial velocity into its x and y components:

v0x = v0 cosθ

v0y = v0 sinθ

We know that one second after the stone is thrown, its velocity in the y direction is 8 m/s, and that it is moving downwards. Using the equation of motion for free fall, we can find the acceleration due to gravity:

v = v0 + at

8 m/s = v0 sinθ - 9.8 m/s^2

Solving for v0 sinθ, we get:

v0 sinθ = 8 m/s + 9.8 m/s^2

v0 sinθ = 17.8 m/s

We can also use the time of flight equation to find the time it takes for the stone to reach its maximum height:

t = 2v0 sinθ / g

Solving for t, we get:

t = 2(17.8 m/s) sinθ / 9.8 m/s^2

t = 3.64 s

The maximum height can then be found using the equation for vertical displacement:

y = v0y t - 1/2 g t^2

At the maximum height, the velocity of the stone is zero, so we can set v0y t - 1/2 g t^2 = 0 and solve for y:

y = v0y^2 / (2g)

Substituting the known values, we get:

y = (v0 sinθ)^2 / (2g)

y = (17.8 m/s)^2 / (2 * 9.8 m/s^2)

y = 16.1 m

Therefore, the initial velocity of the stone is approximately v0 = 19.4 m/s, and its maximum height is approximately 16.1 m.

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User HopeKing
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