Question

need answers for 5, 6,8-10

C) doubled speed v of the wheel center speed. 4. If we push the handle at points A, B and to open the door (with equal forces), and point A at the edge, point C close to the door shaft, and point B at middle, you use the minimum force at point WA B) B C) с 5. (continued with Question 4) No matter how you push the door (different force, different Question 4 rotation speed), the unchanged quantity is A) potential energy B) linear momentum C) torque D) kinetic energy E) moment inertia 6. A snowball rolling down a hill can be regarded as a solid sphere, and more and more snow was stuck on- it. If we think the hill is a flat incline, so the moment inertia of this snow ball will A) increase B) decrease C) be a constant. 7. The necessary condition for a mechanical system to be in equilibrium is A) energy conservation and momentum conservation Question 6 B) energy conservation and net force =0 C) energy conservation and net torque = 0 Obnet force =0 and net torque =0 8. X 110,000 tons air craft carrier can float on water, so a 0.1kg steel ball will A) of course float on water B) sink into water C) float on water or sink into water depends on the ball is on southern hemisphere or northern hemisphere 9. A basket ball falls on ground and bounces up and falls again... A) This is an example of harmonic oscillation B) This is not an example of harmonic oscillation C) If we not consider air resistance, this is an example of harmonic oscillation D) This ball follows Hooke's Law 10. If the dancer stretches her arm, she will A) rotate faster B) rotate slower C) show her beauty but not change her rotation angular speed. Question 10

Answer 1

No matter how you push the door - The mass and the distances will remain constant. Hence u moment of inertia Coption E) will remain Constant. As the snowbau falls down more and more snow stuck on it. Hence it's radias increases . Hence a moment of inertia 1-32² = increases. & A- 160000 tons aircraff can float on water But I kg sted ball will sink into water because Ufff of Archeredes principle: As the dencer streaches his hand, The distance from the rotational axis increases. Hence here mos the with her moment of inestia increases. As I = constant and I increases, this angular speed decreases. Hence she will rotate slower.