Question

The speed of a body revolving in a vertical circle of
radius 7 at the lowest point is 15gr The tension in
the string at the upper most position will be
mg
3 mg
5 mg
Zero​

Answer 1

Answer:

The work needed to be done is 156187 J.

Given :

Initial velocity(u) = 30 km/h = 30 × 5/18 = 25/3 m/s.

Final velocity(v) = 60 km/h = 60 × 5/18 = 50/3 m/s

Mass = 1500 kg

To Find :

Work needed to be done = ?

Solution :

We know the formula to calculate the work done,

So by using it,

➠ Work done = 1/2mv² - 1/2mu²

➠ W = m/2(v²-u²)

➠ W = 1500/2(50/3²-25/3²)

➠ W = 156187 J

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➤ Additional information :

Work is done when a force that is applied to an object moves that object or body!!

The work is calculated by multiplying the force by the amount of movement of an object itself !!

Formula = f × d

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