Question

Calcutate the mass of air passing through the circular area per second on this day (b) On another day, the wind speed is hailf that in (a). (0 Mass- (W) Calculate the power output of the wind turbine on the second day as a fraction of that on the first day Fraction a ball player bounces a ball of mass 0.60 kg. Its centre of mass moves down through a distance of 0.90 m, as shown in Fig. 1.1. Ignore air resistance throughout this question. 4 A 0.90 m Fig. 1.1 Calculate the decrease in gravitational potential energy of the ball as it moves down through the 0.90 m. (a) Decrease in PE .. 12] Page 4 of 6

Answer 1

Decrease in potential energy = mgh = 0.60 times 9.8 times 0.9 Delta PE = 5.292 Joule