A bird weighs 2 kg and is inside a closed cage of 1 kg. If it starts flying, then what is the weight of the bird and cage assembly

Options

A. `1.5` kg
B. `2.5` kg
C. 3 kg
D. 4 kg

Answer

To solve the problem of the bird flying inside a closed cage, we need to analyze the forces and the weight of the system.

### Step-by-Step Solution:

1. **Identify the weights involved**:
- The weight of the bird is given as 2 kg.
- The weight of the cage is given as 1 kg.

2. **Calculate the total weight of the system**:
- The total weight of the bird and the cage assembly is the sum of their individual weights.
- Total weight = Weight of the bird + Weight of the cage
- Total weight = 2 kg + 1 kg = 3 kg.

3. **Understand the effect of the bird flying**:
- When the bird starts to fly, it exerts a downward force on the air inside the cage.
- This downward force is equal to the weight of the bird (2 kg) and is balanced by the air pushing upwards.

4. **Conclusion on the weight of the assembly**:
- The total weight of the bird and cage assembly does not change when the bird flies.
- The weight is still the sum of the individual weights, which is 3 kg.

### Final Answer:
The weight of the bird and cage assembly remains 3 kg, regardless of whether the bird is flying or resting inside the cage.

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