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A bullet is fired from the ground at an angle 45 to the power of ring operator above the horizontal. What initial speed V subscript 0 must the bullet have in order to hit a point 125 meters high located 150 meters away? Use 10 space text m/s end text squared for gravity acceleration.

Respuesta :

Answer:

The initial speed of the bullet is 30 m/s

Explanation:

Given;

angle of projection, θ = 45°

Apply kinematic equation, to determine time to reach vertical height of 125 meters;

Y = V[tex]_y[/tex]t + ¹/₂gt²

At maximum height, v = 0

125 = ¹/₂ x 10t²

125 = 5t²

t² = 125/5

t² = 25

t = √25

t = 5 seconds

Finally, the magnitude of the initial speed of the bullet to reach 150 meters horizontal distance

X = V₀t + ¹/₂gt²

gravity has little or no influence in horizontal displacement

X = V₀t

150 = V₀ x 5

V₀ = 150/5

V₀ = 30 m/s

Therefore, the initial speed of the bullet is 30 m/s

Answer:

The initial speed of the bullet is 79.09 m/s

Explanation:

Given data:

height of the building = 125 m

distance = 150 m

angle = 45°

The velocity of the bullet is:

[tex]y=xtan\theta -\frac{gx^{2} }{2v^{2}cos\theta }[/tex]

Where x and y are horizontal and vertical distances.

[tex]125=150*tan45-\frac{9.8*150^{2} }{2v^{2}*cos45 } \\125=150-\frac{220500}{1.41v^{2} } \\v=79.09m/s[/tex]