1 kg of cotton and iron are weighed in vacuum, then

Options

A. cotton and iron will weight same
B. iron will weight more than cotton
C. cotton will weight more than iron
D. both have zero weight

Answer

To solve the question regarding the weight of 1 kg of cotton and 1 kg of iron in a vacuum, we can follow these steps:

### Step 1: Understand the concept of weight
Weight is defined as the force exerted by gravity on an object. It can be calculated using the formula:
\[ \text{Weight} (W) = \text{mass} (m) \times \text{acceleration due to gravity} (g) \]
where \( g \) is approximately \( 9.8 \, \text{m/s}^2 \) on the surface of the Earth.

### Step 2: Identify the mass of the objects
In this case, we have:
- Mass of cotton, \( m_c = 1 \, \text{kg} \)
- Mass of iron, \( m_i = 1 \, \text{kg} \)

### Step 3: Calculate the weight of cotton
Using the formula for weight:
\[ W_c = m_c \times g = 1 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 9.8 \, \text{N} \]

### Step 4: Calculate the weight of iron
Similarly, for the iron:
\[ W_i = m_i \times g = 1 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 9.8 \, \text{N} \]

### Step 5: Compare the weights
Both weights are equal:
- Weight of cotton = 9.8 N
- Weight of iron = 9.8 N

### Conclusion
In a vacuum, the weight of 1 kg of cotton and 1 kg of iron is the same, which is 9.8 N for each.

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