Question

Rolling Balls LAB - ANSWER SHEET (45 pts)

QUESTIONS:
1. What is the formula for calculating speed? (1 pt)


2. If you were trying to determine if cars in your neighborhood were traveling at or below the posted speed limit, how would you do it? (2 pts)


3. Create a hypothesis as an if-then statement. (2 pts)


4-15. Fill in the Data Table for Balls #1 and #2 (2 pts per blank)
Ball #1 (Describe the ball) - ____________________________________________________
Trial Time to travel 2 meters (seconds)
1
2
3
Average Time




Using the formula s = d/t, calculate the average speed of Ball #1: _____________________

Ball #2 (Describe the ball) - ____________________________________________________
Trial Time to travel 2 meters (seconds)
1
2
3
Average Time




Using the formula s = d/t, calculate the average speed of Ball #2: _____________________

16. Based on your data, which ball was the fastest? (1 pt)
17. Why do you think it was the fastest? (2 pts)
18. Was your hypothesis correct? (1 pt)
19. Do you think size of the ball had anything to do with the speed of the ball? (2 pts)
20. Why or why not? (2 pts)
21. Name 2 factors that could determine the speed at which a ball rolls. (2 pts)

22. A car travels 3 kilometers and it takes 2 minutes to cover that distance What is the speed of the car? (2 pts)
23. A train is traveling at 60 km/hr. It travels for 2 hours. How far will it travel? (2 pts)
24. A girl is riding her bicycle at 10 miles/hour. At the end of the ride she has traveled 35 miles. How long did it take her to cover that distance? (2 pts)

Answer 1

1. s = d/t

22. d = 3km = 3000m

t = 2m = 60s

s = 3000/60

= 300/6

= 50m/s

Therefore, the speed of the car is 50 m/s.

23. s = 60km/hr

t = 2hrs

d = s × t

d = 60 × 2

d = 120km

The car travels for 120km.

24. s = 10mile/hr

d = 35km

t = d/s

t = 35/10

t = 3.5hrs

The girl takes 3.5 hours to cover the distance