How can work and work done be same when work=f x s while work done=weight x height?

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The given formulas for work and work done are related, but they represent slightly different things.

The formula for work is W = F x s, where W is the work done, F is the force applied, and s is the distance over which the force is applied. This formula is used to calculate the amount of energy transferred from one object to another due to the application of a force over a distance.

The formula for work done is Wd = mgh, where Wd is the work done, m is the mass of the object, g is the acceleration due to gravity, and h is the height through which the object is lifted. This formula is used to calculate the amount of energy required to lift an object to a certain height against the force of gravity.

In both cases, the unit of measurement for work and work done is joules (J). However, the two formulas represent different types of work. It is possible for the work done in lifting an object to be equal to the work done by a force applied over a distance.

For example: If you lift a 1 kg book off the ground to a height of 1 meter, you are doing work against the force of gravity.

The work done is Wd = mgh = (1 kg) x (9.81 m/s²) x (1 m) = 9.81 J.

At the same time, the force you apply to lift the book is equal to its weight, which is F = mg = (1 kg) x (9.81 m/s²) = 9.81 N.

If you lift the book over a distance of 1 meter, then the work you do is W = F x s = (9.81 N) x (1 m) = 9.81 J. In this case, the work and work done are equal, but they represent different things.

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How can work and work done be same when work=f x s while work done=weight x height?

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3.
The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.

5.
Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?

6.
Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

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How can work and work done be same when work=f x s while work done=weight x height?

CBSE CLASS XII Related Questions

3. The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.

5.Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?

6.Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

3.
The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.

5.
Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?

6.
Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.