Question

7. Calculate the capacitance to produce ultrasonic waves of 10“ Hz with an inductance of 1
henry.
- 0.0254 PF
b. 0.245 pF
c. 0.0035 pF
d. None of these​

Answer 1

Capacitance is directly proportional to the square of frequency f.

Explanation:

• Frequency is directly proportional to the square root of the product of inductance and capacitance.
• $f = \frac{1}{2\pi } \sqrt{LC}$ , where f is the frequency which is $10^{6}$ Hz, L is inductance which is 1 henry, and C is capacitance which we have to calculate.
• $10^{6} = \frac{1}{2*3.14}\sqrt{1*C}$
• So, C = 0.0254 PF
• It can be seen from the equation that capacitance is directly proportional to the square of frequency f.
• capacitance is inversely proportional to the inductance L
• Hence, capacitance is 0.0254 PF

Answer 2

Answer:

0.0254

Explanation:

Use the formula, f = 1/[2pi (LC)^1/2]

Put the values, 10^6 = 1/[2pi (1*C)^1/2]

Square both terms and rearrange, C = 0.0254PF