Answer:
1) Dimensions of shear rate is ![[T^{-1}]](https://tex.z-dn.net/?f=%5BT%5E%7B-1%7D%5D)
.
2)Dimensions of shear stress are ![[ML^{-1}T^{-2}]](https://tex.z-dn.net/?f=%5BML%5E%7B-1%7DT%5E%7B-2%7D%5D)
Explanation:
Since the dimensions of velocity 'v' are ![[LT^{-1}]](https://tex.z-dn.net/?f=%5BLT%5E%7B-1%7D%5D)
and the dimensions of distance 'y' are ![[L]](https://tex.z-dn.net/?f=%5BL%5D)
, thus the dimensions of 
become
![\frac{[LT^{-1}]}{[L]}=[T^{-1}]](https://tex.z-dn.net/?f=%5Cfrac%7B%5BLT%5E%7B-1%7D%5D%7D%7B%5BL%5D%7D%3D%5BT%5E%7B-1%7D%5D)
and hence the units become 
.
Now we know that the dimensions of coefficient of dynamic viscosity 
are ![[ML^{-1}T^{-1}]](https://tex.z-dn.net/?f=%5BML%5E%7B-1%7DT%5E%7B-1%7D%5D)
thus the dimensions of shear stress can be obtained from the given formula as
![[\tau ]=[ML^{-1}T^{-1}]\times [T^{-1}]\\\\[\tau ]=[ML^{-1}T^{-2}]](https://tex.z-dn.net/?f=%5B%5Ctau%20%5D%3D%5BML%5E%7B-1%7DT%5E%7B-1%7D%5D%5Ctimes%20%5BT%5E%7B-1%7D%5D%5C%5C%5C%5C%5B%5Ctau%20%5D%3D%5BML%5E%7B-1%7DT%5E%7B-2%7D%5D)
Now we know that dimensions of momentum are ![[MLT^{-1}]](https://tex.z-dn.net/?f=%5BMLT%5E%7B-1%7D%5D)
The dimensions of 
are ![[L^{2}T]](https://tex.z-dn.net/?f=%5BL%5E%7B2%7DT%5D)
Thus the dimensions of ![\frac{Moumentum}{Area\times time}=\frac{MLT^{-1}}{L^{2}T}=[MLT^{-2}]](https://tex.z-dn.net/?f=%5Cfrac%7BMoumentum%7D%7BArea%5Ctimes%20time%7D%3D%5Cfrac%7BMLT%5E%7B-1%7D%7D%7BL%5E%7B2%7DT%7D%3D%5BMLT%5E%7B-2%7D%5D)
Which is same as that of shear stress. Hence proved.
Answer:
Disc brake system use a slim rotor and small caliper to halt wheel movement but a drum brake system allow heat to build up inside the drum during heavy braking .
Answer:
4. A series of steps engineers use to solve problems.
Explanation:
The process of engineering design is a sequence of procedures that engineers pursue to arrive at a solution to a specific problem. Most times the solution includes creating a product such as a computer code, which fulfills certain conditions or performs a function. If the project in-hand includes designing, constructing, and testing it, then engineers probably adopt the design process. Steps of the process include defining the problem, doing background research, specifying requirements, brainstorming solutions, etc.
Answer and Explanation:
The DC motor has coils inside it which produces magnetic field inside the coil and due to thus magnetic field an emf is induced ,this induced emf is known as back emf. The back emf always acts against the applied voltage. It is represented by 
The back emf of the DC motor is given by 
Here N is speed of the motor ,P signifies the number of poles ,Z signifies the the total number of conductor and A is number of parallel paths
As from the relation we can see that back emf and speed ar dependent on each other it means back emf limits the speed of DC motor
