Each problem is worth 1 point except for numbers 6 and 9. Number 6 is worth 2 points. Each question in number 9 is worth 1 point.

1. Velcoity Review Problem: A girl can row a boat at a speed of 5 km/h in still water. The girl heads across a river that is 25 km wide. What is the boat's velocity in m/s? How long will it take her to cross the river? Ans: 1.39 m/s, across the river; 18,000 sec
2. If a ball is dropped and attains a velocity of 29.31 m/s in a time interval of 3 sec on another planet, what is the acceleration of gravity on this planet? Ans: 9.77 m/², down
3. A large rock is dropped from a bridge into the river below. If the time required for it to drop is 1.7 sec, with what speed does it hit the water? Ans: 16.66 m/s
4. A runner accelerates from rest at a rate of 1.40 m/s² over a time interval of 8 sec. What is his final velocity? How far dod he travel? Ans: 11.2 m/s, down the track; 44.8 m
5. A car traveling at 4 m/s, south, accelerates at 5 m/s² over a displacement of 114 m, south. What is his final velocity? Ans: 34 m/s, south
6. a woman on a motorcycle moving uniformly at a rate of 60 m/s passes a truck at rest. At the instant the motorcycle passes the truck, the truck begins to accelerate at the rate of 4 m/s². How long does it take the truck to catch up to the motorcycle? How far has the motorcycle traveled? What is the truck's speed at this point? Ans: 30 sec; 1800 m; 120 m/s
7. A mother pushes a baby stroller starting at a speed of 1.50 m/s and accelerates uniformly over a distance of 4.75 m. She attains a velocity of +2.18 m/s. What is the acceleration of the stroller? How long did it take for the stroller to reach this velocity? Ans: +0.26 m/s²; 2.62 s
8. Nathan accelerates his skateboard uniformly along a straight path from rest to 12.5 m/s in 2.5 s. What is Nathan's acceleration? What is Nathan's displacement during this time interval? What is Nathan's average velocity during this time interval? Ans: +5.0 m/s²; +16 m; +6.4 m/s
9. Identify the time interval(s) during which the velocity of the object shown below is constant. Identify the time interval(s) during which the acceleration of the object is constant. Find the value for the average velocity of the object during each time interval in which the object is accelerating. Find the value for the acceleration of the object during each time interval in which the object is accelerating. Identify the interval(s) that the object has zero velocity. Identify the interval(s) when the acceleration of the object is zero. Identify the interval(s) when the object has negative acceleration. What is the displacement of the object during interval B. Ignore acceleration associated with a change in direction.

   

Acceleration Notes

Acceleration Sample Problems