**1. A rocketship coasting at 20,000 m/s in deep space fires its engines so that it accelerates at 20 m/s/s.**

**a) How long will it have to keep accelerating to get to a speed of 300,000 m/s?**

**b) How far will it travel while it is accelerating?**

**2. The head of a rattlesnake can accelerate at 50 m/s/s when it strikes. The rattlesnake’s head starts from rest and accelerates constantly until it strikes a victim that is 0.5 m away.**

**a) How fast is the snake’s head moving when it hits the victim?**

**b) How long does it take the snake’s head to get to the victim?**

**3. A world land speed record was set by Colonel John P. Stapp on March 19, 1954 when he rode a rocket-propelled sled at 283.3 m/s. The sled (and the colonel) was brought to a stop in 1.4s. What acceleration did the colonel experience?**

**4. Ben is inspired by Colonel Stapp’s example to take up rocket sledding. He builds a track so he can get a modern rocket sled to go from rest up to 445 m/s.**

**a) If his track is only 225 m long, how quickly will Ben (and the rocket sled) have to accelerate to reach the target speed by the end of the track?**

**b) How much time will it take the sled to go from one end of the track to the other?**

**5. A high-speed train starts from rest and moves with constant acceleration. As it passes a speed trap, a bored police officer uses a radar gun to measure the train’s speed as 30 m/s. At another speed trap, 160 m further down the track, another officer measures the train’s speed as 50 m/s.**

**a) How quickly was the train accelerating?**

**b) How long did it take to travel the 160 m between speed traps?**

**6. Cole is driving his car at 25.6 m/s along a dark road. As he approaches a bridge, he notices several “Bridge Out” signs and hits the brakes. Two seconds later, the car tumbles over the edge of the missing bridge, 34 m from where he noticed the signs.**

**a) How fast was the car going when it tumbled off the bridge?**

**b) How quickly was the car accelerating while it braked?**

**7. A subway train accelerates gradually (a = 1.2 m/s/s) from rest at one station until it is halfway to the next station and then decelerates gradually (a = -1.2 m/s/s) for the final half of the trip until it comes to rest. The two stations are 1100 m apart.**

**a) What is the maximum speed the train reaches?**

**b) How long does it take to travel between the stations?**

**8. Heather is sitting in her car at a stoplight. At the instant the light turns green, she starts accelerating at 2.2 m/s/s. At the same moment a truck rumbles past her car going a constant speed of 12.2 m/s. Heather is infuriated at being passed by a truck and she keeps accelerating until she gets ahead of the truck.**

**a) How much time will it take her to catch up with the truck?**

**b) How far down the street will she catch up with the truck?**

**c) How fast will she be moving at this point?**