21. Which of the following is a base unit in the SI system?
A) Meter
B) Liter
C) Gram
D) Celsius
22. The unit of magnetic flux density is:
A) Weber
B) Tesla
C) Henry
D) Farad
23. Which instrument is used to measure electric current?
A) Voltmeter
B) Ammeter
C) Ohmmeter
D) Galvanometer
24. The prefix ‘micro-‘ denotes a factor of:
A) 10^-3
B) 10^-6
C) 10^-9
D) 10^-12
25. Which physical quantity is measured in Farads?
A) Inductance
B) Capacitance
C) Resistance
D) Conductance
26. The SI unit of inductance is:
A) Henry
B) Farad
C) Tesla
D) Weber
27. Which of the following is a derived unit?
A) Meter
B) Kilogram
C) Second
D) Newton
28. The unit of electric resistance is:
A) Volt
B) Ampere
C) Ohm
D) Coulomb
29. Which instrument is used to measure length with high precision?
A) Vernier caliper
B) Micrometer screw gauge
C) Meter rule
D) Measuring tape