Motion Numerical based on (Average Velocity, Average Speed)

CBSE PHYSICS

Average Velocity, Average Speed

1. An automobile travels on a straight road for 40 km at 30 km/h. It then continues in the same direction for another 40km at 60km/h. a) What is the average velocity of the car during this 80 km trip? b) What is the average speed.

2. A truck on a straight road starts from rest and accelerates at 2.0 m/s² until it reaches a speed of 20 m/s. Then the truck travels for 20 s at a constant speed until the brakes are applied, stopping the car in a uniform manner in an additional 5.0 s. How long is the truck in motion and what is its average velocity during the motion?

3. While driving home from school you travel at 95 km/h for 130 km then slow to 65 km/h. You get home in 3 hours and 20 min. How far is your hometown from school and what is the average speed?

4. A person takes a trip, driving with a constant speed of 89.5 km/h, except for a 22 min rest stop. If the person's average speed is 77.8 km/h, how much time is spent on the trip and how far does the person travel?

5. From t = 0 to t = 4.21 min, a man stands still, and from t = 4.21 min to t = 8.42 min, he walks briskly in a straight line at a constant speed of 1.91 m/s. In the time interval 1.00 min to 5.21 min what are

a. his average velocity

b. his average acceleration?

6. A bird watcher meanders through the woods, walking 0.684 km due east, 0.486 km due south, and 3.56 km in a direction 61.7 degrees north of west. The time required for this trip is 1.124 h. Determine the bird watcher's (a) displacement and (b) average velocity.

7. A truck driver is in a rush to pick up a load of eggs. She travels 40 miles at 80 mi/h, returning with a full truck along the same route at 40 mi/h. What was her average speed for the trip?

8. A race car driver sets out on a 100-mile race. At the halfway marker, her pit crew radios that she has averaged only 50 mi/hr. How fast must she drive over the remaining distance in order to average 100 mi/hr for the entire race?

9. In reaching her destination, a backpacker walks with an average velocity of 1.34 m/s, due west. This average velocity results because she hikes for 6.44 km with an average velocity of 2.68m/s, due west, turns around, and hikes with an average velocity of 0.447 m/s, due east. How far east did she walk?

10. You jog at 6 mi/h for 5 mi, then you drive another 5 mi in a car. With what average speed must you drive if your average speed for the entire 10 miles is to be 10.8 mi/hr?

11.

a. The distance of one lap around an oval track is 1.50 km. If a biker going at a constant speed makes one lap in 1.10 min, what is the speed of the bike and biker in meters per second?

b. Is the velocity of the bike also constant? Explain.