Explanation :
A power amplifier is used to amplify electric signals i.e. to increase the low power signal to higher powers.
A PNP transistor is connected in a circuit so that the collector-base junction remains reverse biased and the emitter-base junction is forward biased.
This transistor can be used as a power amplifier because it gives a much larger output current. The gain of an amplifier shows the amount of amplification. It is the difference between the input and the output signals.
<h2>
Spring constant is 14.72 N/m</h2>
Explanation:
We have for a spring
Force = Spring constant x Elongation
F = kx
Here force is weight of mass
F = W = mg = 0.54 x 9.81 = 5.3 N
Elongation, x = 36 cm = 0.36 m
Substituting
F = kx
5.3 = k x 0.36
k = 14.72 N/m
Spring constant is 14.72 N/m
<u>Answer:</u>
2N/cm
<u>Step-by-step explanation:</u>
According to the Hooke's Law, the force required to extend or compress a spring is directly proportional distance you can stretch it, which is represented as:
where, 
is the force which is stretching or compressing the spring,
is the spring constant; and
is the distance the spring is stretched.
Substituting the given values to find the elastic constant to get:
Therefore, the elastic constant is 2 Newton/cm.
Answer:
A- A demonstration shows how something works, often including models
Explanation:
A demonstration allows, through experimentation, to show how nature works and in that way can include the explanation of scientific theories that explain the set of observed facts, that is, it serves as a demonstration of the underlying scientific principles.
