Answer:
For any string, we use 
Explanation:
The pumping lemma says that for any string s in the language, with length greater than the pumping length p, we can write s = xyz with |xy| ≤ p, such that xyi z is also in the language for every i ≥ 0. For the given language, we can take p = 2.
Here are the cases:
- Consider any string a i b j c k in the language. If i = 1 or i > 2, we take
and y = a. If i = 1, we must have j = k and adding any number of a’s still preserves the membership in the language. For i > 2, all strings obtained by pumping y as defined above, have two or more a’s and hence are always in the language.
- For i = 2, we can take and y = aa. Since the strings obtained by pumping in this case always have an even number of a’s, they are all in the language.
- Finally, for the case i = 0, we take , and y = b if j > 0 and y = c otherwise. Since strings of the form b j c k are always in the language, we satisfy the conditions of the pumping lemma in this case as well.
Answer:
All the time and to see if someone is behind you.
Explanation:
After you check your side mirrors you should check your review mirror to see who is behind you.
Answer:
(a). the resultant force in the direction of the freestream velocity is termed the drag and the resultant force normal to the freestream velocity is termed the lift
Explanation:
When a fluid flows around the surface of an object, it exerts a force on it. This force has two components, namely lift and drag.
The component of this force that is perpendicular (normal) to the freestream velocity is known as lift, while the component of this force that is parallel or in the direction of the fluid freestream flow is known as drag.
Lift is as a result of pressure differences, while drag results from forces due to pressure distributions over the object surface, and forces due to skin friction or viscous force.
Thus, drag results from the combination of pressure and viscous forces while lift results only from the<em> pressure differences</em> (not pressure forces as was used in option D).
The only correct option left is "A"
(a). the resultant force in the direction of the freestream velocity is termed the drag and the resultant force normal to the freestream velocity is termed the lift
Answer:
1. 
2. 
Explanation:
1.
Given:
- height of the window pane,
- width of the window pane,
- thickness of the pane,
- thermal conductivity of the glass pane,
- temperature of the inner surface,
- temperature of the outer surface,
<u>According to the Fourier's law the rate of heat transfer is given as:</u>
here:
A = area through which the heat transfer occurs = 
dT = temperature difference across the thickness of the surface = 
dx = t = thickness normal to the surface = 
2.
- air spacing between two glass panes,
- area of each glass pane,
- thermal conductivity of air,
- temperature difference between the surfaces,
<u>Assuming layered transfer of heat through the air and the air between the glasses is always still:</u>
Answer:
Suction and exhaust processes do not affect the performance of Otto cycle.
Explanation:
Step1
Inlet and exhaust flow processes are not including in the Otto cycle because the effect and nature of both the process are same in opposite direction.
Step2
Inlet process or the suction process is the process of suction of working fluid inside the cylinder. The suction process is the constant pressure process. The exhaust process is the process of exhaust out at constant pressure.
Step3
The suction and exhaust process have same work and heat in opposite direction. So, net effect of suction and exhaust processes cancels out. The suction and exhaust processes are shown below in P-V diagram of Otto cycle:
Process 0-1 is suction process and process 1-0 is exhaust process.
