Motion WS II Answer on own paper. List variable, rearranged formula, substitution with units and circle answer with units. No Work No Credit No Kidding

1. A rocket takes off from rest from the launching pad. It accelerates to a speed of 150m/s during a time period of 10 seconds. What was the acceleration experienced by the rocket? Ans: 15m/s2 2. You’re driving at 25.8 m/s and slam on your brakes to avoid hitting a deer. It takes 3.6 seconds for your car to stop. A. What is your rate of deceleration? B. If the deer is 50 meters away when you hit the brakes, do you avoid hitting the deer? Prove it by determining distance required to stop. Ans: -7.15m/s2, 46.42m 3. A runner takes off from rest at the starting line. He accelerates to a speed of 8.4 m/s during a time period of 3.2 seconds. What was the acceleration of the runner? Ans: 2.63m/s2 4. A jet plane has an average acceleration of 23.8 m/s2 as it takes off from the ground. If it’s starting velocity as it leaves the ground is 29.4 m/s, what would its velocity be after 16 seconds? What would the final velocity be in km/hr? Ans: 410.2m/s, 1476.72km/hr 5. A boat travels at a velocity of 12.5 m/s for 87 meters. How long (in seconds) does it travel? Ans: 6.96s 6. A boat has an initial speed of 12 m/s. It accelerates at a constant rate of 5m/s2 for 25sec. What distance does it cover as it accelerates during this time? Ans: 1862.5m 7. A car accelerates at a constant rate from 15 m/s to 25 m/s while it travels 125 m. How long does it take to achieve this speed? Ans: 6.25s Hint: This is a 2 step problem 8. You are in your car driving at 32m/s. You need to pass a slow moving truck on the freeway. You accelerate at a constant rate of 0.52m/s2 for 7 seconds as you pass the truck. What distance do you cover during this time? Ans: 236.74m 9. A penny is dropped from the Empire State Building (a height of 426.7 meters). How long does an innocent bystander have to move out of the way, assuming the penny is going to hit him on top of his head, which is 1.7 meters from the ground? Ans: 9.31s 10. A stone dropped from a bridge hits the water below in 7.5 seconds. A. How far above the surface of the water is the bridge? B. Calculate the velocity of the stone when it hits the water. Ans: 275.63m, 73.5m/s 11. A baseball is thrown vertically downward with an initial velocity of 20.0 m/s from a tower 150 meters high. How fast is the baseball moving right before it hits the ground? Ans: 57.79m/s 12. An airplane is traveling due north with a horizontal velocity of 300 m/s. A suitcase belonging to the Pope falls out of the baggage compartment of the plane. If the suitcase hits the ground 17.0 sec later, at what altitude (height) was the plane flying? Disregard air resistance. Ans: 1416.1m