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1.0.0
MCQ
5221. What is the resistance-power of an electric iron with 220V and 1100 watt?
11 Ω
33 Ω
22 Ω
44 Ω
5222. The mains supply of a house is 230V, 50Hz. The potential difference experienced by a person who happens to touch the line is-
230V
325V
460V
115V
5223. What a battery is?
Current source
Power source
Voltage sourcs
None
ব্যাখ্যা: A battery is a device that stores electric power in the form of chemical energy. When necessary the energy a again released as electric power for DC consumers such as lighting and starter motors.
5224. Two charged spheres of radii 10cm and 15cm are connected by a thin wire. No current will flow if they have-
the same charge
the same energy
the same field on their surface
the same potential
ব্যাখ্যাঃ The current flows from higher potential to lower pontential. And if the potential difference is zero, then no current flows through the wire.
5225. Unit of electrical energy is:
Newton-meter
Watt-sec
Watt
BTU
5226. যদি কোনো সার্কিটে Q-একক চার্জ V-ভোল্ট বৈদ্যুতিক চাপে। সেকেন্ড সময়ে প্রবাহিত হয়, তবে কাজের পরিমাণ হয়-
W = VQ
W=VQ/t
W=Vt/Q
W=Qt/V
5227. 1 HP (Horse Power) = ?
746 Watt
0.746 Watt
746 kW
None
5228. The resistivity of the conductor depends on-
area of the conductor
length of the conductor
type of material
none
ব্যাখ্যা: Resistivity depends upon nature of material and physical conditions.
5229. Energy consumption of a 20 Watt bulb for 24 hours is-
48 kWh
480 Wh
480 W
none
5230. Resistance of a conductor of diameter and length L is R ohm. It the diameter of the conductor is halved and its length is doubled the resistance will be-.
2R ohm
4R ohm
8R ohm
3R ohm
5231. What type of material rubber is?
Conductor
Insulator
Semiconductor
Good conductor
ব্যাখ্যা: An insulator is a material that does not conduc electrical current. Insulating materials include-paper plastic, rubber, glass and air.
5232. Which of the following quantites consist of unit as WATT?
force
charge
current
power
ব্যাখ্যা: The St unit of power is the watt and it is discover by the Scottish Engineer James Watt. Power is the rate of consumption of electric energy. So, it is equivalent joules per second.
5233. Resistance depends on:
Cross section
Length
Material
All
5234. The unit of resistivity is-
Ohms
Ohm/Sqm
Ohm-m
None
5235. Which quantity consists of a unit 1 kWh?
energy
power
time
charge
ব্যাখ্যা: 1 kWh is the amount of energy used by a 1 kW (1000 watt) resistance for 1 hour. Energy = Power x Time
5236. কোনো কারখানার সব বৈদ্যুতিক যন্ত্রপাতির জন্য 22kW প্রয়োজন। 220V লাইনের মূল লাইনে উদ্ভূত কত প্রবাহ ধারণক্ষম তার লাগবে?
10A
100A
22A
48A
5237. How many 60-watt bulbs will be safe for a home with main meter of 6 amp and 220 volts?
6
10
11
22
5238. Which one is a semiconductor material?
Phosphorous
Silicon
Rubber
Aluminium
5239. Unit of electrical power is-
Newton meter
Watt
Horse power
Watt-sec
5240. What type of material is Silicon (Si)?
Conductor
Semiconductor
Insulator
Good conductor