Choose the correct statement.

Options

A. Gravitational force is not affected by lntervening medium
B. Electromagnetic force is affected by intervening medium
C. Nuclear force does not obey inverse square law
D. All of these

Answer

To solve the question, we need to analyze each of the statements provided and determine their correctness. Let's go through each statement step by step.

### Step 1: Analyze Statement 1
**Statement 1:** Gravitational force is not affected by the intervening medium.

- Gravitational force is a fundamental force that acts between two masses. It is described by Newton's law of universal gravitation.
- This force is independent of the medium between the masses. It acts at a distance and does not change based on what is in between the two masses.

**Conclusion for Statement 1:** This statement is **correct**.

### Step 2: Analyze Statement 2
**Statement 2:** Electromagnetic force is affected by intervening medium.

- Electromagnetic force includes electric and magnetic forces, which are influenced by the medium through which they act.
- The relative permittivity (dielectric constant) of the medium affects the strength of the electric field and, consequently, the electromagnetic force.

**Conclusion for Statement 2:** This statement is **correct**.

### Step 3: Analyze Statement 3
**Statement 3:** Nuclear force does not obey the inverse square law.

- Nuclear forces, such as the strong and weak nuclear forces, operate at very short ranges (on the order of femtometers).
- Unlike gravitational and electromagnetic forces, which decrease with the square of the distance, nuclear forces do not follow the inverse square law; they remain relatively constant over short distances.

**Conclusion for Statement 3:** This statement is **correct**.

### Step 4: Analyze Statement 4
**Statement 4:** All of these are correct.

- Since we have established that Statements 1, 2, and 3 are all correct, it follows that Statement 4, which claims that all previous statements are correct, must also be correct.

**Conclusion for Statement 4:** This statement is **correct**.

### Final Answer
All statements are correct, therefore the correct choice is **Option 4: All of these are correct**.

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