A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless road. If the banking angle is `45^@`, the speed of the car is

Options

A. `20 ms^(-1)`
B. `30 ms^(-1)`
C. `5 ms^(-1)`
D. `10 ms^(-1)`

Answer

B

Explanation

Here ,`m = 1000 kg , r = 90 m , theta = 45 ^@`
for banking ` tan theta = (v^2)/(Rg)`
`or v= sqrt(Rg tan theta )= sqrt(90 xx10 xx tan 45^@ )= 30 ms^(-1)`