A 66 kg student weighs himself by standing on a scale mounted on a skateboard that is rolling down an incline, as shown.

A 66 kg student weighs himself by standingon a scale mounted on a skateboard that isrolling down an incline, as shown. Assumethere is no friction so that the force exertedby the incline on the skateboard is normal tothe incline.The acceleration of gravity is 9.81 m/s2 .