TEST QUESTION 3-1 Kepler’s second law (law of equal areas) refers to vA: the speed of a planet move around the Sun at different times xB: changes in the area on the surface of the planet at different locations in its orbit xC: the relationship between a planet’s radius and the semi major axis of its orbit xD: all planets’ orbits have elliptical shape

Test question 3-2 If Saturn’s semi major axis is nine times that of the Earth, its period would be xA: same as that of the Earth, xB: three times smaller than that of the Earth, xC: nine times larger than that of the Earth vD: twenty seven times larger than that of the Earth

Test Question 3-3: Galileo’s strongest argument to support the heliocentric model of the solar system is based on his observation of xA: craters on the Moon vB: appearance of Venus at different phases of its orbit xC: Jupiter’s moons also follow Kepler’s third law xD: acceleration of objects falling from the leaning tower of Pisa

Test question 3-4 With force acting on it, a moving object xA: would preserve its momentum vB: may change its direction without changing its speed, xC: change its mass xD: would always come to a halt

Test question 3-5 Arnold Schwarzenegger and Michael J Fox stand on two skate boards and try to push each other apart. Arnold’s mass is three times that of Michael. Arnold xA: accelerates at three times faster than Michael xB: accelerates at the same rate as Michael vC: accelerates at three times slower than xD: stands still.

Test question 3-6 If astronomer A. Jolie lands on a newly discovered planet, Kepler 23 which has twice the radius and the same mass as the earth, her weight would become vA: a quarter of that on the Earth xB: half of that on the Earth xC: same as that on the Earth xD: double that on the Earth.

Test question 3-7 If the Moon halve its distance to the Earth, tides on the Earth would be vA: much stronger xB: remain the same xC: much weaker xD: become chaotic.

Test question 3-8 Suppose a planetary system around a star that is one fourth as massive as our Sun. If that planetary system has a planet with twice the size as Earth orbiting at a distance of 1AU, its orbital period would be xA) eight years xB) four years vC) two years xD) half a year

Test question 3-9 Venus has the same mass as the Earth. But its semi major axis is 0.8 AU and orbital period is 0.7 year. Venus’ angular momentum is xA) 0.56 times that of the Earth xB) 0.8 times that of the Earth vC) 0.9 times that of the Earth xD) same as the Earth