Electronics and Communication Engineering - Measurements and Instrumentation

21.
An oscilloscope has an input impedance consisting of 1 MΩ and 20 pF is parallel. A high impedance probe connected to input of this oscilloscope has a 10 MΩ series resistance. This 10 MΩ series resistance
may not be shunted
should be shunted by 2 pF capacitor
should be shunted by 20 pF capacitor
should be shunted by 200 pF capacitor
Answer: Option
Explanation:
No answer description is available. Let's discuss.

22.
Which of the following is used as detector in audio frequency ac bridges?
AC voltmeter
CRO
Head phones
Vibration galvanometer
Answer: Option
Explanation:
No answer description is available. Let's discuss.

23.

Assertion (A): The gall tinsley potentiometer is a coordinate potentiometer and has two exactly similar potentiometers.

Reason (R): An ac potentiometer may measure the unknown voltage in polar form or rectangular coordinate form.

Both A and R are true and R is correct explanation of A
Both A and R are true but R is not correct explanation of A
A is true R is false
A is false R is true
Answer: Option
Explanation:
No answer description is available. Let's discuss.

24.
If d1, d2, ..., dn are n individual deviations, the standard deviation is
none of the above
Answer: Option
Explanation:
No answer description is available. Let's discuss.

25.
DC voltage of the order of a few mV can be accurately of measured by
PMMC voltmeters
moving iron voltmeter
null balancing potentiometer
electrostatic voltmeter
Answer: Option
Explanation:
No answer description is available. Let's discuss.