Question

A projectile is fired with a velocity \(u\) making an angle \(\theta\) with the horizontal. What is the magnitude of change in velocity when it is at the highest point?

• A. \(u\cos\theta\)
• B. \(u\)
• C. \(u\sin\theta\)
• D. \(u\cos\theta - u\)

Hint:

At the highest point of projectile motion, vertical velocity is zero but horizontal velocity remains unchanged.

Answer 1

The Correct Option is C

Step 1: Initial velocity components: \[ u_x = u\cos\theta,\quad u_y = u\sin\theta \]
Step 2: At the highest point, vertical velocity becomes zero while horizontal remains unchanged.
Step 3: Change in velocity occurs only in vertical direction: \[ \Delta v = u\sin\theta \]