Answer:
To increase the conductivity of the material.
Explanation:
Generally , the group 4 elements are non conductor but in certain conditions, such as doping or the increase in temperature, they becomes conductor.
The doping is the process of mixing of pentavalent or the trivalent material into tetra valent material in the very small amount, so that the material becomes conductor.
In making a diode we need two types of the materials, n type semiconductor and p type semi conductor.
When the trivalent impurity is added in the tetra valent element, the semiconductor becomes n type because an electron is left for the conduction.
When the pentavalent impurity is added in the tetra valent element, the semiconductor becomes p type because a hole is left for the conduction.
Option 4 ( R2 and R3 ) is the correct answer.
Explanation:
- In the below given diagram, we can see a circuit diagram that has four resistors such as R1, R2, R3, and R4.
- The opening of the circuit is noted as "a" and the ending is noted as "b".
- By observing the above diagram, we can clearly see that R2 and R3 are the pair of resistors that are connected in a parallel manner.
- Where all the other resistors such as R1 and R4 are neither connected in parallel nor in series.
Hence we can conclude that Resistor R2 and R3 are the ones that are connected in parallel.
Answer:
(a) F = 15.12 N
(b) a = 30.24 m/s²
(c) To Left
Explanation:
(a)
The magnitude of the spring force is given by Hooke's Law as follows:
F = kx
where,
F = Spring Force = ?
k = Spring Constant = 126 N/m
x = Displacement = A = 0.12 m
Therefore,
F = (126 N/m)(0.12 m)
<u>F = 15.12 N</u>
(b)
The magnitude of acceleration can be found by comparing the spring force with the unbalanced force formula of Newton's Second Law:
F = ma
where,
F = Spring Force = 15.12 N
m = mass of block = 0.5 kg
a = magnitude of acceleration = ?
15.12 N = 0.5 kg (a)
a = 15.12 N/0.5 kg
<u>a = 30.24 m/s²</u>
<u></u>
(c)
Since, the acceleration is always directed towards mean (equilibrium) position in periodic motion. Therefore, the direction of the acceleration at the time of release will be <u>to left.</u>
Work = (force) x (distance)
(550 newtons) x (0.5 meter) = 275 joules each lift .
(275 joules/lift) x (10 lifts) = 2,750 joules of work all together.
Power = (work done) / (time to do the work)
= (2,750 joules) / (20 seconds)
= 137.5 watts . (about 0.18 horsepower)
