Explanation:
Speed of the marathon runner, v = 9.51 mi/hr
Distance covered by the runner, d = 26.220 mile
Let t is the time taken by the marathon runner. We know that the speed of the runner is given by total distance divided by total time taken. Mathematically, it is given by :
t = 2.75 hours
Since, 1 hour = 60 minutes
t = 165 minutes
Since, 1 minute = 60 seconds
t = 9900 seconds
Hence, this is the required solution.
Answer:
Compression in the spring, x = 3.7 cm
Explanation:
It is given that,
Mass of the book, m = 1.6 kg
It can be assumed the spring constant of the spring is, k = 840 N/m
As the book moves down, the change in potential energy of the book is converted to spring potential energy of compression. The mathematical expression is as follows :
x = 0.037 meters
or
x = 3.7 cm
So, the spring is compressed to a distance of 3.7 cm. Hence, this is the required solution.