Question

A car is moving on a circular horizontal track of radius 10m with a constant speed of 10 ms^-1. A plumb bob is suspended from the roof of the car by a light rigid rod of length 10 m. The angle made by the rod with the track is

• A. Zero
• B. 30⁰
• C. 45⁰
• D. 60⁰

Answer 1

Answer: (C)

45⁰

Answer 2

$\frac{mv^{2}}{R}$ = T sin θ and mg = T cos θ

∴ $\frac{v^{2}}{Rg} = \tan\theta$

Thus tan θ = $\frac{10^{2}}{10 \times 10} = 1$ or θ = 45^0h