3. Your professor recalls seeing a saw blade emergency braking system that used electric signals in the saw blade to detect contact with human skin which would cause an aluminum brake to activate against the rim (outer edge) ofthe blade and bring the saw to a complete stop. Looking online, it seems that this process takes only 5 milliseconds.4 Assume someone is cutting a piece of wood using a 0.9 kg circular blade with a diameter of 24 cm that is spinning at 3500 rpm when the brake triggers, bringing the blade to a complete stop. ' a. What is the distance, in radians and cm, traveled by a point on the rim of the blade during the deceleration? b. What is the average magnitude ofthe perpendicular force applied to the blade by the brake? 4. Your plan to disguise yourselfas a pirate has not worked out and now A 30 111 you must walk the plank! You are l standing at point marked C. The plank : 1's nailed onto the deck at point A, and l rests on the support 0.75 m away l from A. The center of mass of the uniform plank is located at point B. Your mass is 65 kg and the mass ofthe plank is 45 kg. What is the minimum downward force the nails must exert on the plank to hold it in place