Two physics professors challenge each other to a 100 m race across a football field. The loser will grade the winner's lab reports for a month. Dr. Nelson runs the race is 10.40s. Dr. Bay runs the first 25.0 m with an average speed of 10.0 m/s, he next 50.0 m with an average speed of 9.50 m/s, and the last 25.0 m with an average speed of 11.1 m/s. Who is the winner?

Question

Physics

Ryan Maddox

2 January, 13:11

Two physics professors challenge each other to a 100 m race across a football field. The loser will grade the winner's lab reports for a month. Dr. Nelson runs the race is 10.40s. Dr. Bay runs the first 25.0 m with an average speed of 10.0 m/s, he next 50.0 m with an average speed of 9.50 m/s, and the last 25.0 m with an average speed of 11.1 m/s. Who is the winner?

+2

Answers (2)

Know the Answer?

Nathen Huffman · Answer 1

If Dr. Nelson's simple average speed all the way is 10.40 m/s

And Dr. Bay's average speed would be x=100 / (10.0/4+9.5/2+11.1/4) = 400/40.1=4000/401=9.9m/s

then he would be first in line

Bowers · Answer 2

Answer: Dr. Nelson

Explanation:

The velocity of Dr. Nelson = Distance of the race / time taken to complete the race

V = 100/10.40 = 9.615m/s

The average velocity of Dr. Bay is

10 + 9.50 + 11.1 / 3 = 10.2m/s

Comparing the average speed of the two racers, Dr. Nelson finished the race with 9.615m/s and Dr. Bay finished with 10.2m/s. Therefore Dr. Nelson won the race