An astronaut on the Moon simultaneously drops a feather and a hammer. The fact that they land together shows that:

Options

A. no gravity forces act on a body in a vacuum
B. the acceleration due to gravity on the Moon is less than on Earth
C. in the absence of air resistance all bodies at a given location fall with the same acceleration
D. the feather has a greater weight on the Moon than on Earth

Explanation

To solve the question, we need to analyze the scenario where an astronaut on the Moon drops a feather and a hammer simultaneously, and they land together. We will evaluate the implications of this observation based on the principles of physics.

### Step-by-Step Solution:

1. **Understanding the Environment**:
- The Moon has a gravitational field, although it is weaker than that of Earth. The acceleration due to gravity on the Moon is approximately \( g/6 \), where \( g \) is the acceleration due to gravity on Earth.

**Hint**: Remember that all celestial bodies with mass exert gravitational force.

2. **Gravitational Force**:
- Since both the feather and the hammer are dropped on the Moon, they are both subject to the Moon's gravitational pull. The fact that they land together indicates that they are both accelerating towards the Moon at the same rate.

**Hint**: Consider how gravity affects objects differently based on their mass in a vacuum.

3. **Absence of Air Resistance**:
- On the Moon, there is no atmosphere, which means there is no air resistance. In a vacuum, all objects fall at the same rate regardless of their mass. This is why the feather and the hammer land together.

**Hint**: Think about how air resistance affects falling objects on Earth versus in a vacuum.

4. **Weight of Objects**:
- The weight of an object is given by the formula \( W = mg \), where \( m \) is the mass and \( g \) is the acceleration due to gravity. On the Moon, the feather's weight is less than its weight on Earth, as it is influenced by the weaker gravitational force.

**Hint**: Recall the relationship between weight, mass, and gravitational acceleration.

5. **Conclusion**:
- The fact that the feather and the hammer land together demonstrates that in the absence of air resistance, all bodies fall with the same acceleration regardless of their mass. Therefore, the correct options are:
- **B**: The acceleration due to gravity on the Moon is less than that on Earth.
- **C**: In absence of air resistance, all bodies in a given location fall with the same acceleration.

### Final Answer:
The correct options are **B** and **C**.

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