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A cow escapes from a hovering UFO. If the UFO is 115 m above a pond, how long will the cow fall before it lands safely in the pond?

User Petomalina
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1 Answer

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Final answer:

The cow will fall for approximately 4.84 seconds before landing in the pond. This is calculated using the kinematic equation for objects in free fall, assuming negligible air resistance.

Step-by-step explanation:

To determine how long the cow will fall before it lands in the pond, we can use the kinematic equation for objects in free fall under the influence of gravity, which assumes no air resistance. Since the cow starts from rest, the initial velocity (vi) is 0, acceleration (a) is equal to the acceleration due to gravity (9.81 m/s2), and the displacement (d) is 115 m downward.

The kinematic equation we will use is:

d = vit + 0.5at2

Plugging in the known values:

115 m = 0 m/s × t + 0.5 × 9.81 m/s2 × t2

Simplify to find (t2):

t2 = 2 × 115 m / 9.81 m/s2

t2 = 23.44469 s2

Take the square root of both sides:

t = √(23.44469 s2)

t ≈ 4.84 s

So, the cow will fall for approximately 4.84 seconds before it lands safely in the pond.

User Mark Murphy
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