MCQOPTIONS
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MCQOPTIONS
This section includes 778 Mcqs, each offering curated multiple-choice questions to sharpen your Physics Mcqs knowledge and support exam preparation. Choose a topic below to get started.
| 301. |
In obtaining an X-ray photograph of our hand we use the principle of______________? |
| A. | photo electric effect |
| B. | ionization |
| C. | shadow photograph |
| D. | any of above |
| Answer» D. any of above | |
| 302. |
Which one of following postulate is in accordance with the Rutherfords model ? |
| A. | continuous spectra for atoms |
| B. | discrete spectra for atoms |
| C. | either continuous nor discrete |
| D. | no spectrum |
| Answer» B. discrete spectra for atoms | |
| 303. |
The electric P.E of an electron in an orbit at a distance rn from the positive charge_____________? |
| A. | Ke2/rn |
| B. | Ke2/rn2 |
| C. | ÀKe2/rn |
| D. | ÀKe2/rn2 |
| Answer» D. ÀKe2/rn2 | |
| 304. |
Ground state energy of the 4th orbit in a H-atom is_____________? |
| A. | 13.60 eV |
| B. | 3.40 eV |
| C. | 0.85 eV |
| D. | 1.51 eV |
| Answer» D. 1.51 eV | |
| 305. |
An alternating current of the r.m.s value of 4.0 A and frequency 50Hz flows in a circuit containing a 10Ω resistor. The peak current is then ? |
| A. | 20A |
| B. | 20.66A |
| C. | 6.66A |
| D. | 5.66A |
| Answer» E. | |
| 306. |
The value of the steady current which when flowing through the same resistor produces heat at the same rate as the mean rate of heat produced by the alternating current is__________________? |
| A. | Average current |
| B. | Sinusoidal current |
| C. | r.m.s current |
| D. | Net current |
| Answer» D. Net current | |
| 307. |
An alternating current or voltage_____________________? |
| A. | fluctuates off and on |
| B. | varies in magnitude alone |
| C. | changes its direction again and again |
| D. | changes its magnitude harmonically and reverses its direction of flow after regularly recurring intervals |
| Answer» D. changes its magnitude harmonically and reverses its direction of flow after regularly recurring intervals | |
| 308. |
Electromagnetic waves travel in free space with the speed of___________________? |
| A. | λ-rays |
| B. | Positive rays |
| C. | Cathode rays |
| D. | More than sound waves |
| Answer» B. Positive rays | |
| 309. |
An electromagnetic wave consists of _____________________? |
| A. | Electric and magnetic fields moving parallel to each other |
| B. | Magnetic field moving with velocity of light in space |
| C. | Electric field moving with velocity of light |
| D. | Electric and magnetic fields moving perpendicular to each other |
| Answer» E. | |
| 310. |
Waves emitted from the antenna are__________________? |
| A. | Sound waves |
| B. | Electromagnetic waves |
| C. | Radio waves |
| D. | Modulated waves |
| Answer» C. Radio waves | |
| 311. |
The minimum wavelength of X-rays produced by the bombardment of electrons on the screen of a television set where the accelerating potential is 2.0K V will be______________? |
| A. | 6.2 x 10-10m |
| B. | 9.1 x 10-18m |
| C. | 3.11 x 10-10m |
| D. | 4 x 10-10m |
| Answer» B. 9.1 x 10-18m | |
| 312. |
If capacitance of L-C circuit is made four times then frequency of the circuit becomes___________________? |
| A. | Twice |
| B. | One half |
| C. | Four times |
| D. | None |
| Answer» C. Four times | |
| 313. |
Michelson devised the formula to calculate the speed of light_______________? |
| A. | C = 4fd |
| B. | C = 8fd |
| C. | C = 16fd |
| D. | C = 5/2fd |
| Answer» D. C = 5/2fd | |
| 314. |
Ratio of the weight of H-atom to that of an electron is approximately______________? |
| A. | 18.336 |
| B. | 1836 |
| C. | 18360 |
| D. | 183.6 |
| Answer» C. 18360 | |
| 315. |
Michelson calculated the speed of light using the instruments______________? |
| A. | spectrometer |
| B. | galvanometer |
| C. | interferometer |
| D. | none of these |
| Answer» B. galvanometer | |
| 316. |
A convex lens acts as a diverging lens if the_________________? |
| A. | object is beyond C |
| B. | if the object is with in C |
| C. | if the object is within f |
| D. | both B and C |
| Answer» E. | |
| 317. |
pure resistor circuit the voltage and current are_______________? |
| A. | Lagging each other |
| B. | They are at 90? phase difference |
| C. | They have zero phase difference |
| D. | No phase difference |
| Answer» D. No phase difference | |
| 318. |
An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ? |
| A. | I = 2I∫Sin(πt/2) |
| B. | I = 2I∫Sin(2πt) |
| C. | I = 2ISinπt |
| D. | I = I∫sin(2πt) |
| Answer» C. I = 2ISinπt | |
| 319. |
The equation θ = 1.22 λ/D was devised by_______________? |
| A. | Newton |
| B. | Einstein |
| C. | Raleigh |
| D. | Planks |
| Answer» D. Planks | |
| 320. |
Electromagnetic waves emitted from antenna are________________? |
| A. | Stationary |
| B. | Longitudinal |
| C. | Transverse |
| D. | All the above |
| Answer» D. All the above | |
| 321. |
Excited atoms return to their ground state in_______________? |
| A. | 10-10s |
| B. | 10-8s |
| C. | 10-6s |
| D. | 10-9s |
| Answer» C. 10-6s | |
| 322. |
The value of critical angle for glass is_______________? |
| A. | 42° |
| B. | 47° |
| C. | 52° |
| D. | 50° |
| Answer» B. 47° | |
| 323. |
A capacitor of capacitance 30µF is charged by a constant current of 10mA. If initially, the capacitor was uncharged what is the time taken for the potential difference across the capacitor to reach 300V ? |
| A. | 0.9sec |
| B. | 15 sec |
| C. | 1.5x105sec |
| D. | 0.9x102sec |
| Answer» B. 15 sec | |
| 324. |
To find the r.m.s value of an alternating current mathematically we need to have ________________? |
| A. | Mean value of I2 |
| B. | Square root of mean value of I2 |
| C. | Square root of I2 |
| D. | Square of 1/2 |
| Answer» C. Square root of I2 | |
| 325. |
A wire of resistance R is coiled inductively so that its inductance is L. The impedance of the coil at a frequency of f is_______________? |
| A. | (R+2πfL) |
| B. | R+1/2πfL |
| C. | (R2+f2L2) |
| D. | (R2+4π2f2L2) |
| Answer» E. | |
| 326. |
If a glass plate is inserted in between the plate of a capacitor in series with a lighted bulb the brightness of the bulb________________? |
| A. | Remains same |
| B. | Brightness increases |
| C. | Brightness decreases |
| D. | No light |
| Answer» C. Brightness decreases | |
| 327. |
In the capacitive circuit the current___________________? |
| A. | Lags behind voltage by π/2 |
| B. | Is in phase with voltage |
| C. | Opposite in phase of voltage by π |
| D. | Leads forward the voltage by π/2 |
| Answer» E. | |
| 328. |
When A.C current passes through a capacitor then the current relationship will be_______________? |
| A. | The current lead voltage by phase angle is 90 degrees |
| B. | The voltage leads current by phase angle is 90 degrees |
| C. | The current lead voltage by phase angle is 45 degrees |
| D. | The voltage leads current by phase angle is 45 degrees |
| Answer» B. The voltage leads current by phase angle is 90 degrees | |
| 329. |
A point where the incident parallel rays of light converge or appear to diverge after passing through a lens is called______________? |
| A. | center of curvature |
| B. | focus |
| C. | optical center |
| D. | aperture |
| Answer» C. optical center | |
| 330. |
Dioptre power of an concave lens of 10 cm focal length is_______________? |
| A. | 10 dioptre |
| B. | 10 dioptre |
| C. | 1 / 10 dioptre |
| D. | 1 / 10 dioptre |
| Answer» C. 1 / 10 dioptre | |
| 331. |
The minimum distance between an object and its real image in a convex lens is_____________? |
| A. | 2 f |
| B. | 2.5 f |
| C. | 3f |
| D. | 4f |
| Answer» E. | |
| 332. |
A convex lens gives a virtual image only when the objects lies_________________? |
| A. | between principal focus and center of curvature |
| B. | beyond 2 f |
| C. | at the principal focus |
| D. | between principal focus and optical center |
| Answer» E. | |
| 333. |
At resonance the value of the power factor in an L-C-R series circuit is_______________? |
| A. | Zero |
| B. | 2 |
| C. | 1 |
| D. | Not definite |
| Answer» D. Not definite | |
| 334. |
If a convex lens of large aperture fails to converge the light rays incident on it to a single point, it is said to suffer from______________? |
| A. | chromatic aberration |
| B. | spherical aberration |
| C. | both spherical and chromatic |
| D. | distortion |
| Answer» C. both spherical and chromatic | |
| 335. |
In optic fiber transmission system _____________ are used regenerate the dim light signal? |
| A. | Diodes |
| B. | Repeaters |
| C. | Laser |
| D. | Transformer |
| Answer» C. Laser | |
| 336. |
Ammeter connected in an AC circuit measures______________? |
| A. | The exact value of the current |
| B. | RMS value of the current |
| C. | The net value of the current |
| D. | The peak value of the current |
| Answer» C. The net value of the current | |
| 337. |
When a pure inductor of inductance L and a pure capacitor of capacitance C are connected in parallel to a sinusoidal potential difference V the potential difference across both L & C will be_______________? |
| A. | Same |
| B. | Different |
| C. | At L will be more than at C |
| D. | At L will be less than at C |
| Answer» B. Different | |
| 338. |
Magnification of the astronomical telescope is_____________? |
| A. | fo+fe |
| B. | fo/fe |
| C. | fe/fo |
| D. | (1+fo/fe)L/fo |
| Answer» C. fe/fo | |
| 339. |
What is the self-inductance of a coil in which an induced emf of 2V is set up when the current changes at the rate of 4 As-1 ? |
| A. | 0.5 mH |
| B. | 0.5H |
| C. | 2.0H |
| D. | 8.0H |
| Answer» C. 2.0H | |
| 340. |
The frequency of a circuit consisting of a capacitance C and a resistor R is________________? |
| A. | C/R |
| B. | R/C |
| C. | 1/RC |
| D. | 1/ 2RC |
| Answer» D. 1/ 2RC | |
| 341. |
A choke is used as a resistance in_________________? |
| A. | DC circuit |
| B. | AC circuits |
| C. | Both AC and DC circuit |
| D. | Full wave rectifier circuit |
| Answer» C. Both AC and DC circuit | |
| 342. |
The phase angle between the voltage and the current in an AC circuit consisting of a resistance is______________? |
| A. | Zero |
| B. | 45° |
| C. | 90° |
| D. | 180° |
| Answer» B. 45° | |
| 343. |
A 10Ω electric heater is connected to a 220V 50Hz mains supply. What is the peak value of the potential difference across the heater element ? |
| A. | 220V |
| B. | 220/ 2V |
| C. | 110V |
| D. | 220 √2V |
| Answer» E. | |
| 344. |
Magnifying power of simple microscope______________? |
| A. | increase with increase in focal length |
| B. | increase with decrease in focal length |
| C. | no effect with decrease or increase with focal length |
| D. | list distance of distinct vision |
| Answer» C. no effect with decrease or increase with focal length | |
| 345. |
A vector can be multiplied by a number. The number may be_______________? |
| A. | Dimensionless |
| B. | Dimensional scalar |
| C. | Negative |
| D. | All A, B and C are correct |
| Answer» E. | |
| 346. |
Maximum number of rectangular components are_____________? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» D. 4 | |
| 347. |
The least distance of distinct vision for a normal eye is_______________? |
| A. | 15 cm |
| B. | 25 cm |
| C. | 30 cm |
| D. | 40 cm |
| Answer» C. 30 cm | |
| 348. |
Final image produced by a compound microscope is_____________? |
| A. | real and inverted |
| B. | real and erect |
| C. | virtual and erect |
| D. | virtual and inverted |
| Answer» E. | |
| 349. |
In multimode step index fibre the refractive index of core and cladding is____________? |
| A. | same |
| B. | different |
| C. | zero |
| D. | different with refractive index of core higher than cladding |
| Answer» E. | |
| 350. |
A convex lens of focal length f1 and a concave lens of focal length f2 are placed in contact. The focal length of the combination is_____________? |
| A. | f2 + f1 |
| B. | f2 – f1 |
| C. | f1f2/f2+f1 |
| D. | f1f2/f1-f2 |
| Answer» E. | |