A body weighs 60 kg on the earth's surface . What would be its weight at the centre of the earth ?

Options

A. `60kgwt`
B. 6kgwt
C. `60x9.8kgwt`
D. Zero

Explanation

To solve the problem of finding the weight of a body at the center of the Earth, we can follow these steps:

### Step 1: Understand the Weight of the Body on the Surface of the Earth
The weight of a body is given by the formula:
\[ W = m \cdot g \]
where:
- \( W \) is the weight,
- \( m \) is the mass of the body,
- \( g \) is the acceleration due to gravity at the Earth's surface.

Given that the body weighs 60 kg on the surface, we can calculate its weight in newtons. However, it's important to note that the weight is actually a force, and mass should be converted to weight using the acceleration due to gravity.

### Step 2: Calculate the Weight on the Surface
Assuming \( g \approx 10 \, \text{m/s}^2 \) for simplicity, we calculate:
\[ W = 60 \, \text{kg} \cdot 10 \, \text{m/s}^2 = 600 \, \text{N} \]
So, the weight of the body on the surface of the Earth is 600 N.

### Step 3: Understand the Concept of Weight at the Center of the Earth
As we move towards the center of the Earth, the acceleration due to gravity \( g \) decreases. At the center of the Earth, the gravitational field strength is zero. This means that the weight of any object at the center of the Earth will also be zero.

### Step 4: Conclude the Weight at the Center of the Earth
Since the acceleration due to gravity at the center of the Earth is zero, we can conclude:
\[ W = m \cdot g = 60 \, \text{kg} \cdot 0 \, \text{m/s}^2 = 0 \, \text{N} \]

### Final Answer
The weight of the body at the center of the Earth is **0 N**.

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