The automobile travels from a parking deck down along a cyli

The automobile travels from a parking deck down along a cylindrical spiral ramp at a constant speed. If the ramp descends a distance of 12 m for every full revolution, which of the following quantities is not zero?

a_z

a_?

a_r

None of the above

Solution

Here, the radial acceleration ar is not zero as it is directed towards the centre and helps the car to take circular trajectory.Rest all accelerations are zero as speed is constant.