Draw a sketch of the pattern of field lines due to a:
(a) current flowing into a circular coil,
(b) solenoid carrying current.

Explanation

To solve the question, we will draw the magnetic field lines for two scenarios: (a) a current flowing into a circular coil and (b) a solenoid carrying current. Here’s a step-by-step text solution:

### Step 1: Drawing the Circular Coil
1. **Sketch the Circular Coil**: Begin by drawing a circle to represent the circular coil. Indicate the direction of the current flowing through the coil (e.g., clockwise or counterclockwise).
2. **Label the Terminals**: Mark the terminals of the coil, indicating the positive and negative sides of the battery connected to the coil.
3. **Draw Magnetic Field Lines**: From the center of the coil, draw concentric circles around the coil to represent the magnetic field lines. These lines should be denser near the coil and spread out as they move away from it.

### Step 2: Indicating the Direction of the Magnetic Field
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