Which of the following is weakest force in nature?

Options

A. Gravitational force
B. Electrostatic force
C. Magnetic force
D. All of these

Explanation

To determine which of the following is the weakest force in nature, we need to analyze the three forces mentioned: gravitational force, electrostatic force, and magnetic force.

### Step-by-Step Solution:

1. **Understanding the Forces**:
- **Gravitational Force**: This is the force of attraction between two masses. It is described by the formula \( F_g = \frac{G \cdot m_1 \cdot m_2}{r^2} \), where \( G \) is the gravitational constant (\( 6.67 \times 10^{-11} \, \text{N m}^2/\text{kg}^2 \)), \( m_1 \) and \( m_2 \) are the masses, and \( r \) is the distance between their centers.
- **Electrostatic Force**: This is the force between charged particles, given by Coulomb's law \( F_e = \frac{k \cdot |q_1 \cdot q_2|}{r^2} \), where \( k \) is Coulomb's constant, \( q_1 \) and \( q_2 \) are the charges, and \( r \) is the distance between them.
- **Magnetic Force**: This is the force exerted by magnets when they attract or repel each other. It is dependent on the magnetic fields and the distance between the magnets.

2. **Comparing the Strengths**:
- The gravitational force is very weak compared to the electrostatic and magnetic forces. This is because the gravitational force depends on the mass of the objects involved, and for small masses, this force is extremely small.
- For example, if we take two 1 kg masses separated by 0.1 m, the gravitational force calculated is very small (approximately \( 6.67 \times 10^{-10} \, \text{N} \)).
- In contrast, electrostatic and magnetic forces can be significantly stronger, especially when dealing with charged particles or magnets.

3. **Conclusion**:
- Based on the analysis, the gravitational force is the weakest force in nature when compared to electrostatic and magnetic forces. Therefore, the answer to the question is **gravitational force**.