# displacement vector and distance

Hello I need help answering these problems.

Peter noticed a bug crawling along a meter stick and decided to record the bug's position in five-second intervals. After the bug crawled off the meter stick, peter created the table shown.

1. What is the displacement of the bug between t = 0.00 s and t = 20.0 s?

2. what is the total distance that the bug traveled between t = 0.00 s and t = 20.0 s? Assume the bug only changed the directions at the end of the five-second interval.

3. Which one of the physical quantities listed below is not correctly paired with its SI unit and dimensions?

4. A car travels in a straight line covering a total distance of 90.0 miles in 60.0 minutes. Which one of the following statements concerning this situation is necessarily true?

5. A canadian goose flew 845 km from Southern California to Oregan with an average speed of 30.5 m/s. How long, in hours, did it take the goose to make this journey?

6. Carl Lewis set a world record for the 100.0-m run with a time of 9.86 s. If, after reaching the finish line, Mr. Lewis walked directly back to his starting point in 90.9 s, what is the magnitude of his average velocity for the 200.0 m?

7. An elevator is moving upward with a speed of 11 m/s. Three seconds later, the elevator is still moving upward, but its speed has been reduced to 5.0 m/s. what is the average magnitude of the elevator during the 3.0 s interval?

8. Which one of the following is not a vector quantity?

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#### Solution Preview

Please see the attached file.

1. the displacement is always , where df is the final position, di is the initial position.

So the displacement d = 65.7 - 49.6 = 16.1 cm

Answer: e

2. From t = 0 to 5s, the bug was crawling to the left direction (assume right direction is positive along the x-axis). So it traveled cm.

From t = ...

#### Solution Summary

This solution is comprised of a detailed explanation of questions involving displacement vector, distance, average velocity, and average acceleration. It has a '5/5' rating.

Classical mechanics problems - vectors operations and uniform acceleration

13. A bus travels at an average speed of 90 km/h. On average, how far does the bus travel in 20 min? Is this distance the magnitude of the actual displacement of the bus? Explain.

17. A student runs 30 m east, 40 m north, and 50 m west.

(a) The magnitude of the student's net displacement is (1) between 0 and 20 m, (2) between 20 m and 40 m, or (3) between 40 m and 60 m?

(b) What is his net displacement?

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21. (a) Given that the speed of sound is 340 m / s and the speed of light is 3.00 X 10 m/s

(186 000 mi / s), how much time will elapse between a lightning flash and the resulting thunder if the lightning strikes 2.50 km away from the observer?

(b) Does your answer change if you assume the light travels with an infinite speed (i.e., the lightning flash is seen instantaneously)?

25. An earthquake releases two types of traveling waves, called "transverse" and "longitudinal." The average speeds of transverse and longitudinal seismic waves in rock are 8.9 km / s and 5.1 km / s, respectively. A seismograph records the arrival of the transverse waves 73 s before that that of the longitudinal waves. Assuming that the waves travel in straight lines, how far away is the center of the earthquake from the seismograph?

37. An automobile traveling at 25.0 km / h along a straight, level road accelerates to 65.0 km / h in 6.00 s. What is the magnitude of the auto's average acceleration?

55. The driver of a pickup truck going 100 km / h applies the brakes, giving the truck a

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uniform deceleration of 6.50 m / s while it travels 20.0 m.

(a) What is the speed of the truck in kilometers per hour at the end of the distance?

(b) How much time has elapsed?

61. A bullet traveling horizontally at a speed of 350 m / s hits a board perpendicular to the surface, passes through it, and emerges on the other side at a speed of 210 m / s. If the board is 4.00 cm thick, how long does the bullet take to pass through it?

87. A stone is thrown vertically downward at an initial speed of 14 m / s from a height of 65 m above the ground.

(a) How far does the stone travel in 2.0 s?

(b) What is its velocity just before it hits the ground?