A person holds on a weight of `10 kg` at a height of `5m` above the ground for 5 minutes. Work done by him is

Options

A. zero
B. `50J`
C. `250J`
D. `300J`

Answer

To solve the problem of calculating the work done by a person holding a weight of 10 kg at a height of 5 m above the ground for 5 minutes, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Weight of the Object:**
The weight (force due to gravity) of the object can be calculated using the formula:
\[ \text{Weight} = m \cdot g \]
where \( m = 10 \, \text{kg} \) (mass of the object) and \( g = 9.81 \, \text{m/s}^2 \) (acceleration due to gravity).
\[ \text{Weight} = 10 \, \text{kg} \cdot 9.81 \, \text{m/s}^2 = 98.1 \, \text{N} \]

2. **Understand the Concept of Work Done:**
Work done is defined as the product of the force applied and the displacement in the direction of the force. The formula for work done is:
\[ W = F \cdot d \cdot \cos(\theta) \]
where \( W \) is work done, \( F \) is the force, \( d \) is the displacement, and \( \theta \) is the angle between the force and the direction of displacement.

3. **Analyze the Situation:**
In this scenario, the person is holding the weight stationary at a height of 5 m. Therefore, the displacement of the weight in the vertical direction is 0, as it is not moving up or down.

4. **Calculate the Work Done:**
Since the displacement \( d = 0 \):
\[ W = F \cdot d \cdot \cos(\theta) = 98.1 \, \text{N} \cdot 0 \cdot \cos(0) = 0 \, \text{J} \]
Thus, the work done by the person is 0 Joules.

5. **Conclusion:**
The work done by the person holding the weight at a constant height for any duration (5 minutes in this case) is zero because there is no displacement.

### Final Answer:
The work done by the person is **0 Joules**.