On August 10, 1972, a large meteorite skipped across the atmosphere above the western United States and western Canada, much like a stone skipped across water. The accompanying fireball was so bright that it could be seen in the daytime sky and was brighter than the usual meteorite trail. The meteorite's mass was about 3.8 x 106 kg; it's speed was about 16 km/s. Had it entered the atmosphere vertically, it would have hit Earth's surface with about the same speed. (a) Calculate the meteorite's loss of energy (as a positive number, in joules) that would have been associated with the vertical impact. (b) Express the energy as a multiple of the explosive energy of 1 megaton of TNT, which is 4.2 x 1015 J. (c) The energy associated with the atomic bomb explosion over Hiroshima was equivalent to 13 kilotons of TNT. To how many Hiroshima bombs would the meteorite impact have been equivalent? (a) Number i Units (b) Number i Units (c) Number i Units >

For years, the tallest tower in the United States was the Phoenix Shot Tower in Baltimore, Maryland. The shot tower was used from 1828 to1892 to make lead shot for pistols and rifles and molded shot for cannons and other instruments of warfare. Molten lead was dropped from the top of the 82.15 m tall tower into a vat of water. During its free fall, the lead would form a perfectly spherical droplet and solidify. Determine the velocity of the droplet right before it hits the ground. (Note: acceleration = -9.81 m/s/s) (Hint: think about the direction the droplet travels when considering its displacement.) ___________m/s

A spaceship with m = 1.00 ✕ 104 kg is in a circular orbit around the Earth, h = 800 km above its surface. The ship's captain fires the engines in a direction tangent to the orbit, and the spaceship assumes an elliptical orbit around the Earth with an apogee of d = 3.00 ✕ 104 km, measured from the Earth's center. How much energy (in J) must be used from the fuel to achieve this orbit? (Assume that all the fuel energy goes into increasing the orbital energy and that the perigee distance is equal to the initial radius.)

Consider an object that is in an elliptical orbit with semimajor axis a = 7.9×106 m about a planet of mass M = 1.0×1023 kg. (a) What is the speed of the object when it is closest to the planet at r = a/4? (b) What is the speed of the object when it is furthest from the planet?