A point source that emits wave uniformly in all directions, produces wavefronts that are

Options

A. spherical
B. elliptical
C. cylindrical
D. planar

Answer

To solve the question, we need to analyze the behavior of a point source emitting waves uniformly in all directions. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Point Source
A point source is an idealized source that emits waves uniformly in all directions. This means that the waves radiate outward from the source in a spherical manner.

**Hint:** Visualize a light bulb in a dark room; it emits light in all directions.

### Step 2: Visualize the Wavefronts
When a point source emits waves, the wavefronts are the surfaces over which the wave has a constant phase. For a point source, these wavefronts are not flat but rather curved.

**Hint:** Think of ripples created when a stone is thrown into a still pond; the ripples represent wavefronts.

### Step 3: Determine the Shape of the Wavefronts
Since the waves are emitted uniformly in all directions, the wavefronts formed will be spherical. Each wavefront is a sphere centered at the point source.

**Hint:** Imagine the point source as the center of a balloon; as you inflate the balloon, the surface represents the wavefronts.

### Step 4: Confirm the Perpendicularity of Wavefronts to Rays
Wavefronts are always perpendicular to the direction of wave propagation (the rays). In the case of a point source, the rays extend radially outward from the source to the surface of the spherical wavefront.

**Hint:** Picture arrows (rays) pointing outward from a center point to the surface of a sphere.

### Conclusion
Thus, the wavefronts produced by a point source that emits waves uniformly in all directions are spherical.

**Final Answer:** The wavefronts are spherical.

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