Q1. A rocket-powered sled starts from rest on a frozen lake that is 8 miles across. The sled then accelerates at +20 ft/s for 2 minutes. Then, the rockets are shut off and the sled coasts with a constant velocity of 2400 ft/s. If the total distance traveled by the sled is 432000 feet in a time of 3 minutes, find how long the sled was coasting.
Q2. In 1920, a thoroughbred racehorse named Man O'War ran the Preakness Stakes in 1 minute and 44 seconds. The Preakness is 9.5 furlongs in length (1furlong=201.168m). What was the acceleration (in SI units) of the horse if he reached a maximum speed of 50 miles per hour after the first two furlongs and slowed down at a constant rate of .45m/s2 after crossing the finish line?