The work done by a satellite in a complete orbit is

Options

A. infinity
B. unity
C. zero
D. negative

Explanation

To find the work done by a satellite in a complete orbit, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Work Done**:
Work done (W) is defined as the product of force (F) and displacement (s) in the direction of the force. Mathematically, it is expressed as:
\[ W = F \cdot s \]

2. **Analyzing the Motion of the Satellite**:
A satellite in orbit is continuously moving around a central body (like Earth) due to gravitational force. This motion is circular, and the satellite is in a state of free fall.

3. **Displacement in a Complete Orbit**:
When the satellite completes one full orbit, it returns to its original position. Therefore, the total displacement of the satellite after one complete orbit is zero.

4. **Calculating Work Done**:
Since the displacement (s) is zero, we can substitute this into the work done formula:
\[ W = F \cdot 0 = 0 \]

5. **Conclusion**:
The work done by the satellite in a complete orbit is zero. This is because even though the satellite is under the influence of gravitational force, it does not move from its starting point to a different point in space.

### Final Answer:
The work done by a satellite in a complete orbit is **0 Joules**.

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