SSC CGL PHYSICS Question Answer Part - 5 (Q. No. 201-250)
201. The resistance of an ideal voltmeter is
(a) zero
(b) very low
(c) very high
(d) infinite
202. The resistance of an ideal ammeter is
(a) zero
(b) very low
(c) very high
(d) infinite
203. Two bulbs are fitted in a room in the domestic electric installation. One of them glows brighter than the other. Then
(a) the brighter bulb has smaller resistanc
(b) the brighter bulb has larger resistance
(c) both the bulsbs have the same resistance
(d) none of these
204. The heating element of an electric heater should be made of a material having
(a) high specific resistance and high melting point
(b) high specific resistance and low melting point
(c) low specific resistance and low melting point
(d) low specific resistance and high melting point
205. When a body is earth conncected, electrons from the earth flow into the body. This means the body is
(a) charged negatively
(b) an insulator
(c) uncharged
(d) charged positively
206. Current provided by a battery is maximum when
(a) internal resistance is equal to external resistance
(b) internal resistance is greater than external resistance
(c) internal resistance is less than external resistance
(d) none of these
207. Fuse wire should have
(a) low resistance, high melting point
(b) low resistance, low melting point
(c) high resistance, low melting point
(d) high resistance, high melting point
208. If ahigh power heater is connected to electric mains, then the bulbs in the house become dim because there is a
(a) current drop
(b) potential drop
(c) no current drop
(d) no potential drop
209. Metals are good conductor of heat than insulator because
(a) their atoms are relatively aprt
(b) they contain free electron
(c) they have reflecting surface
(d) none of these
210. Which of the following is not the cause of low conductivity of electrolyte
(a) Low drift velocity of ions
(b) High resistance offered by the solution of the motion of ions
(c) Low number of density of charge carriers
(d) Ionization of salt
211. Good resistance coils are made of
(a) Copper
(b) manganin
(c) gold
(d) silver
212. The primary cell is a
(a) secondary cell
(b) primary cell
(c) both (a) and (b)
(d) None of these
213. When a charged particle entres a uniform magnetic field its kinetic energy
(a) Remains constant
(b) increased
(c) Decreases
(d) becomes
214. The core of an electromagnet is made of soft iron because soft iron has
(a) small susceptibility and small retentivity
(b) large susceptibility and small retentivity
(c) large density and large retentivity
(d) small density and large retentivity
215. Vibration magnetometer works on the principle of
(a) torque acting on the bar magnet
(b) force acting on the bar magnet
(c) both the force and the torque acting on the bar magnet
(d) none of these
216. Farraday’s law of electromagnetic induction is related to the
(a) law of conservation of charge
(b) law of conservation of energy
(c) third law of motion
(d) none of these
217. A motor converts
(a) mechanical energy into electrical energy
(b) mechanical energy into sound energy
(c) electrical energy into mechanical energy
(d) None of these
218. The Dynamo converts
(a) Electrical energy into Mechanical Energy
(b) Mechanical energy into
(c) Mechanical energy into Electrical Energy
(d) None of these
219. A switch is always connected to the
(a) earth wire (b) neutral wire
(c) line wire (d) None of these
220. A fuse wire is characterized by
(a) Low resistance and high melting point
(b) High resistance and high melting point
(c) High resistance and low melting point
(d) Low resistance and low melting point
221. A carbon microphone is best used in
(a) Dynamo
(b) telephone
(c) Transformer
(d) None of these
222. Alternating current can be measured by
(a) Moving coil galvanomenter
(b) Hot wire ammeter
(c) Tangent galvanometer
(d) None of these
223. The phenomenon of electromagnetic induction implies a production of induced
(a) resistance in a coil when the magnetic field changes with time
(b) current in a coil when an electric field changes with time
(c) current in a coil when a magnetic field changes with time
(d) voltage in a coil when a magnetic field changes with time
224. What is the difference between a CFL and an LED LAMP?
(1) Toproduce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi- conductor material.
(2) The average life span of a CFL is much longer than of and LED lamp.
(3) A CFL is LESS energy –efficient as compared to an LED lamp.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3
(c) 1 and 3
(d) 1, 2 and 3
225. A permanent magnet repels
(a) ferromagnetic substances only
(b) diamagnetic substances only
(c) paramagnetic susstances only
(d) both paramagnetic and diamagnetic substances
226. A fuse is used in an electric circuit to-
(a) Break the circuit when excessive current flows through the circuit
(b) Break the circuit when power gets off
(c) Indicate if the current is flowing uninterrupted
(d) Complete the circuit for flow of current
227. Electricity is produced through dry cell from
(a) Chemical energy
(b) Thermal energy
(c) Mechanical energy
(d) Nuclear energy
228. The unit of electrical power is
(a) Volt
(b) Watt
(c) Kilowatt hour
(d) Ampere
229. When you walk on a woolen carpet bring your finger near the metallic handle of a door an electric shock is produced.
This is because
(a) charge is transferred from your body to the handle
(b) the temperature of the human body is higher than of the handle
(c) A chemical reaction occurs when you touch the hanle
(d) The human body and the handle arrive at thermal equilibrium by the process
230. The product of conductivity and resistivity of a conductor
(a) Depends on pressure applied
(b) Depends on current flowing through conductor
(c) is the same for all conductors
(d) Varies from conductor to conductor
231. Who invented the battery?
(a) Volta
(b) Roentgen
(c) Faraday
(d) Maxwell
232. The mass number of an atom is determined by-
(a) Adding the number of neutrons and number of electrons
(b) Adding the number of protons and number of electrons
(c) The number of protons only
(d) Adding the number of neutrons and number of protons
233. Particle which can be added to the nucleus of an atom without changing its chemical properties are
(a) Electrons
(b) protons
(c) Neutrons
(d) alfa – particles
234. The least penetrating power ray is
(a) alfa Ray
(b) X – Ray
(c) gamma Ray
(d) beta Ray
235. Heavy water is used as moderator a nuclear reactor. The function of the moderator is
(a) to control the energy released in the reactor
(b) to absorb neutrons and stop the chain reaction
(c) to cool the reactor
(d) to slow down the neutrons to thermal energy
236. The main source of enrgy in Sun is:
(a) Nuclear fusion
(b) Nuclear fission
(c) Chemical reaction
(d) Mechanical energy
237. The most penetrating radiation out of the following is
(a) X - rays
(b) alfa – rays
(c) beta - rays
(d) gamma – rays
238. The method of age determination called “radioactive uranium dating” cannot be used to determine the age of
(a) rocks
(b) fossils and plant bodies
(c) the earth
(d) minerals on earth
239. In the nuclear reactors, moderators are used to:
(a) Slow down the neutrons
(b) Generate neutrons
(c) Accelerate neutrons
(d) Absorb the neutrons
240. The process of emission of electrons from metal by UV rays is-
(a) Photoelectric emission
(b) Thermionic emission
(c) Secondary emission
(d) Field emission
241. X- rays are ………. waves.
(a) Longitudinal
(b) Transverse
(c) Electromagnetic
(d) Elastic
242. An intrinsic semiconductor at absolute zero temperature is a
(a) Superconductor
(b) good conductor
(c) Perfect insulator
(d) none
243. Chernobyl Nuclear Plant, now decommissioned is in
(a) Russia
(b) Ukrain
(c) Belarus
(d) Georgia
244. U -235 belongs to which member of the series?
(a) Neptunium series
(b) Thorium series
(c) Actinium series
(d) Uranium series
245. gamma - ray consists of:
(a) Meson particles
(b) Neutrino particles
(c) Higg’s boson
(d) Electromagnetic waves
246. A diode as a rectifier converts
(a) Ac to dc
(b) dc to ac
(c) Varying dc into constant dc
(d) High voltage into low voltage and vice-versa
247. A digital signal possesses:
(a) Continuously varying values
(b) only two discrete values
(c) Only four discrete values
(d) None of the above
248. A digita signal:
(a) is less reliable than analog signal
(b) is more reliable than analog signal
(c) is equally reliable as the analog signal
(d) None of the above
249. For television broadcasting the frequency employed is normally
(a) 30 – 300 MHz
(b) 30 – 300 GHz
(c) 30 – 300 kHz
(d) 30 – 300 Hz
250. Who invented the mobile phone?
(a) Raymond Samuel Tomlinson
(b) Marlin Cooper
(c) Chuck Hull
(d) Tim Berners – Lee
Answer Key
