Question

As a skater spreads her mass out, her rotational speed a) increases b) decreases c) remains the same If the distance between two planets doubles, the gravitational attraction between them a) doubles b) stays the same c) halves d) quarters If the radius of a satellites orbit doubles, its period a) increases by 1.4 b) doubles c) increases times 2.8 d) quadruples If the mass bouncing on a spring doubles, the period of the bounce a) doubles b) increases times 1.4 c) quadruples d) halves If the mass of a pendulum increases, the period of its swing a) halves b) remains the same c) doubles d) quadruples The speed of a wave a) is proportional to its frequency b) is proportional to its wavelength c) both a and b d) neither a nor b Where a fluid flows faster its pressure is a) lower b) the same c) higher d) whether the pressure is higher or lower depends on the fluids density A piece of copper with a volume of 100 cc has a buoyant force of 1 N when it is under water. Aluminum has a density one-third of copper's. The buoyant force on a 100 cc piece of aluminum is a) 0.33 N b) 1 N c) 2 N d) 3 N It is possible to add heat to an object, but its temperature doesn't change, a) True b) False It is possible to raise the temperature of an object without adding any heat to it. a) True b) False A tank of gas has 3000 joules of heat added to it and it expands doing 2000 joules of work. The change in internal energy of the gas is a) 1000 b) 5000 c) - 1000 d) - 5000 joules A 100 grams of copper at 100 C is put into 100 grams of water at 20 C. The final temperature the mixture will be a) less than 60 b) 60 c) more than 60

Answer 1

4. Rotational speed will decrease 5. Gravitational force is inversely proportional to the square of distance between two masses so it will be quarters 6. Time period is T = 2pir/v so if double T will get double 7. Period of mass will gets multiply by 1.4 because its time period is given by T = 1/2pi squareroot m/R 8. It will remain the same as it did not depend upon the mass of pendulum