Practice Test: Question Set - 04
1. For making a capacitor, it is better to select a dielectric having
- (A) Low permittivity
- (B) High permittivity
- (C) Permittivity same as that of air
- (D) Permittivity slightly more than that of air
2. Which of the following statements is correct?
- (A) Air capacitors have a black band to indicate
the outside foil
- (B) Electrolytic capacitor must be connected in the
correct polarity
- (C) Ceramic capacitors must be connected in the correct
polarity
- (D) Mica capacitors are available in capacitance
value of 1 to 10 pF
3. The sparking between two electrical contacts can be reduced by inserting a
- (A) Capacitor in parallel with contacts
- (B) Capacitor in series with each contact
- (C) Resistance in line
- (D) None of the above
4. The capacity of capacitor bank used in power factor correction is expressed in terms of
- (A) kW
- (B) kVA
- (C) kVAR
- (D) Volts
5. Which of the following statements is incorrect?
- (A) The thinner the dielectric, the more the
capacitance and the lower the voltage breakdown rating for a capacitor
- (B) A six dot mica capacitor color coded white,
green, black, red and yellow has the capacitance value of 500 pF
- (C) Capacitors in series provide less capacitance but a
higher voltage breakdown rating for the combination
- (D) A capacitor can store charge because it has
a dielectric between two conductors
6. The potential gradient across the material of low permittivity is than across the material of high permittivity.
- (A) Smaller
- (B) Greater
- (C) Both (A) and (B)
- (D) None of the above
7. At a point is equal to the negative potential gradient at that point.
- (A) Electric intensity
- (B) Electric flux
- (C) Magnetic flux
- (D) Magnetic flux density
8. What will happen to an insulating medium if voltage more than the breakdown voltage is applied on it?
- (A) It will become magnetic
- (B) It will melt
- (C) It will get punctured or cracked
- (D) Its molecular structure will get changed
9. The ohmmeter reading for a short circuited capacitor is
- (A) Infinity
- (B) Few kilo ohms
- (C) Few mega-ohms
- (D) Zero
10. A positive and a negative charge are initially 50 mm apart. When they are moved close together so that they are now only 10 mm apart, the force between them will be
- (A) 5 times smaller than before
- (B) 5 times greater than before
- (C) 10 times greater than before
- (D) 25 times larger than before
Next Test:
Blogger Comment
Facebook Comment