A particle moves in a circle of radius 20 cm. Its linear speed is given by v=2t, where t is in second and v in metre/ second. Find the radial and tangential acceleration at t=3s.

Options

A. `220 m//"sec"^(2), 50 m//"sec"^(2)`
B. `100 m//"sec"^(2), 5 m//"sec"^(2)`
C. `120 m//"sec"^(2), 2 m//"sec"^(2)`
D. `110 m//"sec"^(2), 10 m//"sec"^(2)`

Answer

C

Explanation

`v = 2t`
`a_(t) = (dv)/(dt) = 2 m//s^(2)`
`a_(r) = v^(2)/r rArr a_(r) , t = 3 sec = [2(3)]^(2)/0.3 = 36/0.3 =120 m//s^(2)`