1. An aluminum casting that weighs 10 pounds sits on a steel surface. How much force will be necessary to get it to start sliding? The static coefficient of friction (mu) for aluminum on steel is 0.61.
2. A robot arm must be able to extend 87 cm in 3 s. while carrying a load of 6 kg. How much force is required in Newtons?
3. A torque of 15 N-m is applied to a rotating part. The moment of inertia is 0.078 kg-m2. How much time (in seconds) will it take to rotate the part 90 degrees?
4. A small gasoline engine can put out 12,000 N-m/min of mechanical power. The engine is used to drive an electrical generator that is 60 percent efficient. 1 N-m = 2.78 X 10-4 W-h. Find the output of the generator in Watts.
5. A proportional controller for a rotating antenna has a gain of Kp of 5 in-oz/deg. The antenna was initially pointing south, but was then commanded to point southeast. Find the torque applied to the antenna in in-oz, when the antenna is within 5 degrees of southeast.
6.The steering wheel has backlash. This means there is a delay between the time the wheel is turned, and the time the car responds. The driver tends to overturn, which leads to instability and lack of control of the car. In the presence of backlash, discuss what steps the operator can take to reduce the instability.