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sergejj [24]
3 years ago
9

A ball which is dropped from the top of a building strikes the ground with a speed of 30m/s. Assume air resistance can be ignore

d. The height of the building is approximately
Physics
1 answer:
Vika [28.1K]3 years ago
3 0

Answer:

               h= 45.87 m.

Explanation:

Data given:

Vf= 30m/s ,     and we know that g = 9.8 m/s²    

The ball has an initial velocity of zero      Vi = 0 m/s²    

To Find:

Height of the building = ?

Solution:

       According to 3rd law of the motion;

                                      2aS= Vf² - Vi²                      ( S= h , a=g)

                                     2*9.81*h = (30)² - (0)²

                                      h= 45.87 m.

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Answer:

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Explanation:

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3 years ago
A 25N force is acting on a body moving on a straight line with Initial momentum 20 kam's. Find the final momentum after 4 second
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The final momentum of the body is equal to 120 Kg.m/s.

<h3>What is momentum?</h3>

Momentum can be described as the multiplication of the mass and velocity of an object. Momentum is a vector quantity as it carries magnitude and direction.

If m is an object's mass and v is its velocity then the object's momentum p is: {\displaystyle \mathbf {p} =m\mathbf {v} . The S.I. unit of measurement of momentum is kg⋅m/s, which is equivalent to the N.s.

Given the initial momentum of the body = Pi = 20 Kg.m/s

The force acting on the body, Pf = 25 N

The time, Δt = 4-0 = 4s

The Force is equal to the change in momentum: F ×Δt = ΔP

25 × 4 = P - 20

100 = P - 20

P = 100 + 20 = 120  Kg.m/s

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Explanation:

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3 years ago
Which applications, either for diagnostic purposes or for therapeutic purposes, do not involve ionizing radiation? Check all tha
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Flying against the wind, an airplane travels 2670 km in 3 hours. Flying with the wind, the same plane travels 11,070 km in 9 hou
xxMikexx [17]

Answer:

speed of plane in still air = 1060 km/h

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Explanation:

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and va = 1230 - vp = 1230 - 1060 = 170 km/h

5 0
3 years ago
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