If a current is passed in a spring then

Options

A. it is compressed
B. it gets expanded
C. it performs a vertical SHM
D. remains unchanged

Answer

To solve the question "If a current is passed in a spring then...", we need to analyze the behavior of the spring when an electric current flows through it. Here’s a step-by-step solution:

### Step 1: Understanding the Setup
When a current flows through a spring, we are essentially dealing with a coil of wire. The spring can be thought of as a series of loops or coils that can interact with each other when current flows through them.

**Hint:** Consider how current in a coil generates a magnetic field.

### Step 2: Magnetic Field Generation
When an electric current passes through a coil (or spring), it generates a magnetic field around it. The direction of the magnetic field can be determined using the right-hand rule.

**Hint:** Remember that current creates a magnetic field that can exert forces on other currents.

### Step 3: Interaction Between Adjacent Coils
In the case of a spring, the adjacent coils will experience a magnetic force due to the current flowing through them. If the currents in the adjacent coils are in the same direction, they will attract each other.

**Hint:** Think about how two parallel wires carrying current interact with each other.

### Step 4: Resulting Motion of the Spring
Since the adjacent coils attract each other, this results in a compressive force acting on the spring. As a result, the spring will compress due to the attractive forces between the adjacent coils.

**Hint:** Visualize how the coils would move closer together when they are attracted.

### Step 5: Conclusion
Based on the analysis, when a current is passed through a spring, the spring will be compressed due to the attractive forces between the adjacent coils.

**Final Answer:** The spring is compressed (Option A).