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Muhammad wishes to shoot an arrow through the open window of a tall building. The window is 32.8 meters above the ground and Muhammad stands 63.6 meters from the base of the building. If Muhammad aims the arrow at an angle of 51.5 degrees above the horizontal, with what minimum speed must he fire the arrow in order for it to enter the window?

User Bristi
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Muhammad must fire the arrow with a minimum speed of approximately 29.42 m/s to have it enter the window.

To solve this problem, we can use the principles of projectile motion. The arrow's motion can be divided into horizontal and vertical components. The horizontal component of the arrow's velocity remains constant, while the vertical component is affected by gravity. We aim to find the minimum initial velocity required for the arrow to enter the window at a height of 32.8 m.

Given:

Vertical displacement (window height) = 32.8 meters

Horizontal distance to the building = 63.6 meters

Launch angle = 51.5 degrees

Acceleration due to gravity (g) = 9.81 m/s²

We can break down the initial velocity (V₀) of the arrow into horizontal (V₀x) and vertical (V₀y) components:

V₀x = V₀ * cos(θ)

V₀y = V₀ * sin(θ)

Where θ is the launch angle in radians (θ = 51.5° * π / 180).

The time of flight (t) of the arrow can be determined from the vertical motion:

t = √(2 * Δy / g)

Where Δy is the vertical displacement (32.8 meters).

The horizontal distance covered by the arrow during this time can be found using the horizontal component of velocity:

Δx = V₀x * t

Since we want the arrow to hit the building at a horizontal distance of 63.6 meters, we need to set up an equation for Δx and solve for the initial velocity (V₀):

Δx = 63.6 meters

Δx = V₀x * t

63.6 = V₀ * cos(θ) * t

Substitute the expression for time (t) from the equation for the time of flight:

63.6 = V₀ * cos(θ) * √(2 * Δy / g)

Now, solve for V₀:

V₀ = 63.6 / (cos(θ) * √(2 * Δy / g))

Plug in the values:

θ = 51.5° * π / 180

Δy = 32.8 meters

g = 9.81 m/s²

Calculate V₀:

θ = 51.5° * π / 180 = 0.8988 radians

V₀ = 63.6 / (cos(0.8988) * √(2 * 32.8 / 9.81))

V₀ ≈ 29.42 m/s

So, Muhammad must fire the arrow with a minimum speed of approximately 29.42 m/s to have it enter the window.

User Gelgamil
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