Which of the following is correct about **uniform acceleration**?

Question

Accepted Answer

**Solution:**

1. **An object under free fall** experiences a constant acceleration due to gravity, approximately $9.8 	ext{ m/s}^2$ downward. This acceleration remains constant in magnitude and direction, making it a classic example of **uniform acceleration**.

2. **An object moving on a frictionless surface** will maintain its velocity if no external force acts on it (Newton's first law). It does not necessarily have uniform acceleration unless a constant force is applied. Hence, this statement is not always true.

3. **An object moving with constant speed** in a straight line has zero acceleration because velocity magnitude and direction are constant. If moving in a circle at constant speed, it has centripetal acceleration, which is not uniform acceleration as the direction of acceleration changes continuously.

4. **Motion of a spring** (simple harmonic motion) involves acceleration proportional to displacement and directed towards equilibrium. This acceleration changes in magnitude and direction continuously, so it is not uniform acceleration.

**Answer:** An object under free fall is an example of uniform acceleration.

Answer

Answer

Answer