Answer:
(a) 0.063 m/s
(b) 1.01 m/s
Explanation:
rate of volume flow, V = 4 x 10^-6 m^3/s
(a) radius, r = 4.5 x 10^-3 m
Let the speed of blood is v.
So, V = A x v
where A be the area of crossection of artery
4 x 10^-6 = 3.14 x 4.5 x 10^-3 x 4.5 x 10^-3 x v
v = 0.063 m/s
Thus, the speed of flow of blood is 0.063 m/s .
(b) Now r' = r / 4 = 4.5 /4 x 10^-3 m = 1.125 x 10^-3 m
Let the speed is v'.
So, V = A' x v'
4 x 10^-6 = 3.14 x 1.125 x 10^-3 x 1.125 x 10^-3 x v'
v' = 1.01 m/s
Thus, the speed of flow of blood is 1.01 m/s .
Answer:

Explanation:
Given:
- mass of solid disk,

- radius of disk,

- force of push applied to disk,

- distance of application of force from the center,

<em>For the condition of no slip the force of static friction must be greater than the applied force so that there is no skidding between the contact surfaces at the contact point.</em>

where:
= static frictional force




Answer:
t = 6.17 s
Explanation:
For a 1 revolution movement, 
Torque, 
Moment of Inertia, 
If the wheel starts from rest, 
The angular displacement of the wheel can be given by the formula:
................(1)
Where
is the angular acceleration

To get t, put all necessary parameters into equation (1)

it will move the object if you apply force, because of that it will stay the same with newton's law.