Question

A motor car is travelling at 30 ms^-1 on a circular road of radius 500 m. It is increasing speed at the rate of 2 ms^-2. The acceleration of car is

• A. 2 ms^-2
• B. 2.7 ms^-2
• C. 3ms^-2
• D. 3.7 ms^-2

Answer 1

Answer: (B)

2.7 ms^-2

Answer 2

Given a_T = 2 ms^-2

and a_r = $\frac{v^{2}}{r} = \frac{30 \times 30}{500} = 1.8ms^{- 2}$

∴ a = $\sqrt{a_{r}^{2} + a_{t}^{2}} = \sqrt{1.8^{2} + 2^{2}}$ = 2.7 ms^-2