26. A metal bar of mass M and length & can rotate in a horizontal PS plane about a vertical, frictionless axle through its center. A at hollow channel down the bar allows compressed air (fed in at the axle) to spray out of two small holes at the ends of the bar, as shown. The bar is found to speed up to angular velocity a in a time interval A, starting from rest. What force does each escaping jet of air exert on the bar? a. On the figure, draw vectors to show the forces exerted on the bar. Then label the moment arms of each force. b. The forces in your drawing exert a torque about the axles. Write an expression for each torque, and then add them to get Top view the net torque. Your expression should be in terms of the unknown force F and "known" quantities such as M, L, g, etc. c. What is the moment of inertia of this bar about the axle? d. According to Newton's second law, the torque causes the bar to undergo an angular acceleration. Use your results from parts b and c to write an expression for the angular acceleration. Simplify the expression as much as possible. e. You can now use rotational kinematics to write an expression for the bar's angular velocity after time Ar has elapsed. Do so. f. Finally, solve your equation in part e for the unknown force. This is now a result you could use with experimental measurements to determine the size of the force exerted by the gas.