The mass of Mars is `( 1//9) `times that of the earth and its radius is `( 1//2)` that of the earth. What is the weight of a body having a mass of 100kg on the surface of the earth?

Explanation

To find the weight of a body having a mass of 100 kg on the surface of the Earth, 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:
\[ \text{Weight} (W) = m \cdot g \]
where \( m \) is the mass of the object and \( g \) is the acceleration due to gravity.

### Step 2: Identify the mass of the body
Given that the mass of the body is:
\[ m = 100 \, \text{kg} \]

### Step 3: Determine the acceleration due to gravity on Earth
The standard value of the acceleration due to gravity on Earth is:
\[ g \approx 9.81 \, \text{m/s}^2 \]

### Step 4: Calculate the weight of the body on Earth
Using the formula for weight:
\[ W = m \cdot g \]
Substituting the values we have:
\[ W = 100 \, \text{kg} \cdot 9.81 \, \text{m/s}^2 \]
\[ W = 981 \, \text{N} \]

### Final Answer
The weight of the body having a mass of 100 kg on the surface of the Earth is:
\[ \text{Weight} = 981 \, \text{N} \]

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