Answer:
Option A
The cost of keeping the semiconductor below the critical temperature is unreasonable
Explanation:
First of all, we need to understand what superconductors are. Superconductors are special materials that conduct electrical current with almost zero resistance. This means that there is little or no need for a voltage source to be connected to them. As a matter of fact, once a superconductor is connected to a power supply, one can remove the power supply and the current will still flow.
However, most superconducts can only conduct at very low temperatures up to -200 degrees Celcius. This is because, at that temperature, their atoms and molecules are relatively settled, hence they pose little or no resistance to the flow of current.
This as you can guess is extremely difficult to do, as you will need a lot of effort to cool it to that temperature and maintain it.
This makes option a the answer:
The cost of keeping the semiconductor below the critical temperature is unreasonable.
Answer:
उव्ग्वुव ह्व्झ एउएइहे एइएइएइएएइ सिसुब्स्सी बीस सिस इस्ब एइब
Explanation:
?उग्व्ब्वु विब्सिए इसिग्व विद्बिअब्द सिह्व्व इस्ब्व दिव्ब्स विह्द ऐद्जिइ सुउगव्दी सिइगैगे क्ज्गैइव अजिव्व्ज्व्स कैह्द अजि ह्ज्फ्ज इअह इकुगै ईग इअबे अजिव्ब जैइअब इऐहे ऐइहे ऐइग्गे अत्व्ब ओप्झब रोज दिधिए ऊइफ्ब इसुहद ईउहे सिउउअ दिइब्द स्सिउए ऐइहे सिएय्व एउविये एइव्वे
Answer:
<em>No, a rigid body cannot experience any acceleration when the resultant force acting on the body is zero.</em>
Explanation:
If the net force on a body is zero, then it means that all the forces acting on the body are balanced and cancel out one another. This sate of equilibrium can be static equilibrium (like that of a rigid body), or dynamic equilibrium (that of a car moving with constant velocity)
For a body under this type of equilibrium,
ΣF = 0 ...1
where ΣF is the resultant force (total effective force due to all the forces acting on the body)
For a body to accelerate, there must be a force acting on it. The acceleration of a body is proportional to the force applied, for a constant mass of the body. The relationship between the net force and mass is given as
ΣF = ma ...2
where m is the mass of the body
a is the acceleration of the body
Substituting equation 2 into equation 1, we have
0 = ma
therefore,
a = 0
this means that<em> if the resultant force acting on a rigid body is zero, then there won't be any force available to produce acceleration on the body.</em>
<em></em>
Answer:
<em>The final speed of the second package is twice as much as the final speed of the first package.</em>
Explanation:
<u>Free Fall Motion</u>
If an object is dropped in the air, it starts a vertical movement with an acceleration equal to g=9.8 m/s^2. The speed of the object after a time t is:
And the distance traveled downwards is:
If we know the height at which the object was dropped, we can calculate the time it takes to reach the ground by solving the last equation for t:
Replacing into the first equation:
Rationalizing:
Let's call v1 the final speed of the package dropped from a height H. Thus:
Let v2 be the final speed of the package dropped from a height 4H. Thus:
Taking out the square root of 4:
Dividing v2/v1 we can compare the final speeds:
Simplifying:
The final speed of the second package is twice as much as the final speed of the first package.
