Answer:
8 times
Explanation:
Given that You have about 10 quarts of blood in your body. At REST your heart pumps about 5 quarts each minutes.
That means the heart will pump 10 quarts in 2 minutes.
That is half of your blood volume per minute.
If during exercise it can pump 40 quarts per minute, that is, 80 quarts in 2 minutes.
To know how many times does all of your blood complete the cycle around your body during exercise, you must divide 80 quarts by 10 quarts. That is,
80 / 10 = 8
Therefore, your blood complete the cycle around your body 8 times during the exercise.
Answer:
This is known as a Galilean transformation where
V' = V - U
Where the primed frame is the Earth frame and the unprimed frame is the frame moving with respect to the moving frame
V - speed of object in the unprimed frame
U - speed of primed frame with respect to the unprimed frame
Here we have:
V = -15 m/s speed of ball in the moving frame (the truck)
U = -20 m/s speed of primed (rest) frame with respect to moving frame
So V' = -15 - (-20) = 5 m/s
It may help if you draw a vector representing the moving frame and then add
a vector representing the speed of the ball in the moving frame.