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A body of mass m tied to a string is lowered at a constant acceleration of (g/4) through a vertical distance h. the work done by the string will be

a. 3/4 Mgh
b. 1/4 Mgh
c. -3/4 Mgh
d. -1/4 Mgh

1 Answer

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Final answer:

The work done by the string in lowering the body is -1/4 Mgh. The work done by the string while lowering the body can be found using the formula: "Work equals force multiplied by distance."

Step-by-step explanation:

The work done by the string in lowering the body can be calculated using the equation:

W = Fd

Where:

W is the work done,

F is the force applied by the string,

d is the distance through which the body is lowered.

Given that the body is lowered at a constant acceleration of (g/4), the force applied by the string can be calculated using Newton's second law (F = ma).

Since the body is being lowered, the force applied by the string is opposite to the gravitational force acting on the body. Therefore, F = -mg.

The distance through which the body is lowered is given as h.

Substituting the values into the equation W = Fd, we get:

W = -mg × h

Since g is the acceleration due to gravity, which is approximately 9.8 m/s², the work done by the string can be written as:

W = -mg

Therefore, the correct option is d. -1/4 Mgh.

User Mahfuzul Alam
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