आधारभूत विद्युत् (Basic Electrical) – Basic Electrical Engineering MCQ

आधारभूत विद्युत् (Basic Electrical): प्रश्न र उत्तर

सही लागेको विकल्पमा थिच्नुहोस्। सही भए हरियो, गलत भए रातो देखिन्छ; ३ सेकेन्डपछि सही उत्तर र व्याख्या देखिन्छ।

सही: ० / ०

411. An SMD resistor is marked '4R7'. Its resistance is:

     क47 Ω ख470 Ω ग4.7 kΩ घ4.7 Ω
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

412. The thermal (overload) tripping element of a miniature circuit breaker works with a:

     कbimetallic strip that bends when heated by sustained overcurrent खsolenoid that acts instantly on short circuits गcapacitor that discharges घfusible wire that melts
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

413. An automatic voltage stabiliser (AVR) connected before a refrigerator is used to:

     कchange the supply frequency खconvert AC into DC गkeep the output voltage nearly constant when the mains voltage varies घstore energy during power cuts
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

414. The characteristic hum of a transformer at twice the supply frequency is mainly caused by:

     कcorona discharge खeddy currents in the windings गmagnetostriction of the core laminations घarcing at the terminals
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

415. When several loaded cables are bunched together in one conduit, their current rating must be reduced (derated) because:

     कthe voltage between them rises खheat cannot be dissipated as easily, so the insulation could overheat गtheir resistance becomes zero घthe supply frequency changes
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

416. A battery management system (BMS) in a lithium-ion battery pack mainly:

     कmonitors and protects the cells against over-voltage, under-voltage, over-current and over-temperature, and balances them खreplaces the need for a charger गconverts the battery's DC into AC घincreases the energy density of the cells
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

417. In a solar home system, the main function of the charge controller is to:

     कstore energy खconvert DC to AC for appliances गincrease the panel's output voltage beyond its rating घprevent the battery from being overcharged or deeply discharged
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

418. Bypass diodes are connected across groups of cells in a solar panel to:

     कconvert DC into AC खstop the battery discharging into the panel at night गincrease the open-circuit voltage घlet current flow around shaded cells, reducing power loss and hot spots
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

419. The power rating of a solar module expressed in watt-peak (Wp) is its DC output under standard test conditions, i.e. an irradiance of:

     क1000 W/m² at a cell temperature of 25 °C ख1000 W/m² at 100 °C ग500 W/m² at 50 °C घ100 W/m² at 0 °C
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।

420. A digital multimeter on its voltage range usually loads a circuit much less than an ordinary analogue (moving-coil) voltmeter because it has:

     कno internal battery खa mirror scale गa very high input resistance (typically about 10 MΩ) घa very low input resistance
     💬 टिप्पणी / गल्ती रिपोर्ट (०)

     छलफल / प्रश्न उत्तरमा गल्ती छ

     पठाउनुहोस्

     टिप्पणी जाँचपछि मात्र देखिन्छ।