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3 years ago

A projectile is fired with an initial velocity of 450 feet per second at an angle of 70° with the horizontal.

Physics

1 answer:

pav-90 [236]3 years ago

5 0

<h2>After 26.28 seconds projectile returns 26.28 seconds.</h2>

Explanation:

Initial velocity = 450 ft/s = 137.16 m/s

Angle, θ = 70°

Consider the vertical motion of projectile,

When the projectile return to the ground we have

Displacement, s = 0 m

Acceleration, a = -9.81 m/s²

Initial velocity, u = 137.16 x sin70 = 128.89 m/s

Substituting in s = ut + 0.5 at²

s = ut + 0.5 at²

0 = 128.89 x t + 0.5 x (-9.81) x t²

t² - 26.28 t = 0

t ( t- 26.28) = 0

t = 0 s or t = 26.28 s

After 26.28 seconds projectile returns 26.28 seconds.

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3 years ago

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Black_prince [1.1K]

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3 years ago

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Natalija [7]

Answer:

option (i) is correct

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3 years ago

A plant is thrown straight

olchik [2.2K]

The time taken for the plant to hit the ground from a distance of 7.01m and at a velocity of 8.84m/s is 1.59s.

<h3>How to calculate time?</h3>

The time taken for a motion to occur can be calculated using the following formula:

v² = u² - 2as

Where;

v = final velocity
u = initial velocity
s = distance
a = acceleration

8.84² = 0² + 2 × a × 7.01

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a = 5.57m/s²

V = u + at

8.84 = 0 + 5.57t

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Learn more about time at: brainly.com/question/13170991

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ivann1987 [24]

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