A body has a mass M kg on the earth .What will be its weight on the earth ?

Options

A. Mg newton
B. `((M)/(8))` newton
C. M newton
D. Zero

Answer

To find the weight of a body with mass \( M \) kg on 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 is calculated using the formula:

\[ W = m \cdot g \]

where:
- \( W \) is the weight,
- \( m \) is the mass of the object,
- \( g \) is the acceleration due to gravity.

### Step 2: Identify the Mass
In this case, the mass \( m \) of the body is given as \( M \) kg.

### Step 3: Use the Value of Acceleration Due to Gravity
The standard value of acceleration due to gravity \( g \) on the surface of the Earth is approximately \( 9.8 \, \text{m/s}^2 \).

### Step 4: Substitute the Values into the Formula
Now we can substitute the values into the weight formula:

\[ W = M \cdot g \]
\[ W = M \cdot 9.8 \, \text{m/s}^2 \]

### Step 5: Write the Final Expression for Weight
Thus, the weight of the body on Earth can be expressed as:

\[ W = 9.8M \, \text{N} \]

where \( W \) is in newtons (N).

### Conclusion
The weight of a body with mass \( M \) kg on Earth is \( 9.8M \, \text{N} \).

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