Question

A motorcyclist riding in a vertical sphere does not lose contact with the sphere at the highest point. If the minimum angular velocity at which the motorcyclist achieves this is $1.5rad/s$, what is the radius of the sphere? (in $m$)

• A. $4.45$
• B. $4.36$
  
• C. $1.36$
  
• D. $5.36$
  

Answer 1

The correct option is B $4.36$

$\text{centrifugal force = weight}$

$mr{w}^2=mg$

$r=g/w^2=9.8/{1.5}^2=4.36m$