Question

A particle is going with constant speed along a uniform helical and spiral path separately as shown in figure

• A. The velocity of the particle is constant in both cases
• B. The magnitude of acceleration of the particle is constant in both cases
• C. The magnitude of acceleration is constant in (a) and increasing in (b)
• D. The magnitude of accleration is decreasing continuously in both the cases

Answer 1

Answer: (C)

The magnitude of acceleration is constant in (a) and increasing in (b)

By observing both the figure we see that in fig (A) radius will remain constant while in fig (B) radius will vary as the particle complete one circumference.

$a=v^2/r$

Given $v$ is constant and $r$ reduces in spiral path. Hence, $a$ increases in spiral path.