8:05 WS1 CenterOfMass Center of mass worksheet 45 1) Define center of mass. 2) How is center of mass related to inertia? 3) How is center of mass related to the force of gravity? 4) When is a free-standing object stable? 5) When is a free-hanging object stable (will not move when released)? 6) A father and his young son get on a teeter-totter. The son sits 2 m from the center, but the father has to sit closer to balance. Where does the father have to sit to balance the teeter-totter if he weighs 4 times as much as his son? 7) On a meter stick, like in our lab activity, there are masses hanging on both sides of a pivot point. On the left are masses of 3 g at 0.20 m and 10 g at 0.40 m from the center. On the right is a 6 g mass at 0.50 m from the center. Where would a 4 g mass have to be hung to make the meter stick balance? 8) Two masses are hanging from the ends of a 1 m bar. Where should the force of tension be placed such that the system hangs without rotating, a) relative to m1? b) relative to m2. mi is 1 kg, m2 is 3 kg. Ignore the mass of the bar between the two masses. 9) Same as the previous question, but m is 2 kg and m2 is 3 kg. mi m2 10) Same as the previous question, but m is 20 kg and m2 is 50 kg and the masses are each 1 cm in from the ends of the bar, so they're 0.98 m apart. 11) A person is standing on the very end of a 2 m long board that is level and balanced. The balance point is 0.20 m from the end the person is on. The board has a mass of 20 kg. a) What is the mass of the person? b) How much does the person weigh? 12) A 98 N person is standing on a board, 1 m from the end. The board is balanced on a point that is 2m from the same end. The board is 49 N. How long is the board overall? 13) Describe three methods to find the center of mass of this L-shaped piece of cardboard. Draw diagrams to help your explanation. 14) Challenge question: Where is the center of mass of the object in the preceding question if the length of the sides of the squares is 1 m? Give numbers. 15) Challenge question: A honeybucket man is carrying his load. He has a pole 2 m long with a bucket hanging from each end. The buckets have a mass of 2 kg each. The pole has a mass of 1 kg. The front bucket has 5 kg of "honey" in it, and the rear bucket has 3 kg of "honey." How far from the center of the pole is the honeybucket man's shoulder? AP1 Unit 10 Rotation - WS1 CenterOfMass.docx 1 3/19/19