Question

A particle moves with uniform speed along a circular path. The direction of its acceleration (if any) is-

• A. Radially outward
• B. Radially inward
• C. Tangentially
• D. No acceleration

Hint:

In circular motion:

• Velocity is always tangential to the path.

• Centripetal acceleration is always directed toward the center.

• If speed is constant, only the direction of velocity changes.
Hence, uniform circular motion is an accelerated motion.

Answer 1

The Correct Option is B

Step 1: Understand what acceleration means.
Acceleration is the change in velocity over time. Velocity has both a size (speed) and a direction.

Step 2: Look at the motion.
The particle moves around a circle at a steady speed. At each point its velocity points along the tangent to the circle.

Step 3: Notice the direction keeps changing.
As the particle goes around, the tangent direction turns. So even though the speed stays the same, the direction of velocity changes all the time.

Step 4: Decide if acceleration exists.
Since the velocity direction changes, the velocity itself changes. A changing velocity means there is acceleration. So yes, acceleration is present.

Step 5: Find its direction.
This acceleration is called centripetal acceleration. It always points toward the centre of the circle, which means radially inward. \[ a = \frac{v^2}{r} \]

Step 6: Choose the answer.
The acceleration points toward the centre. \[ \boxed{\text{Radially inward}} \]