physics MCQs – Page 33

Practise multiple-choice questions from physics for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

physics Mcqs

641. Which one is the derived quantity in SI units _____________?
0

A. Plane angle

B. Electric charge

C. Electric current

D. Amount of substance

642. The dimension of force is__________________?
0

A. MLT-2

B. MLT-1

C. ML-1T-2

D. ML-1T

643. The unit of force is _________ and its symbol is ______________ Which is the correct pair ?
0

A. Newton, n

B. newton, N

C. newton, n

D. Newton, N

644. The radiations emitted form hydrogen filled discharge tube show____________?
0

A. line spectrum

B. continuous spectrum

C. absorption spectrum

D. band spectrum

645. X-ray are________________?
0

A. of unknown nature

B. radio isotopes

C. high energy electrons

D. high energy photons

646. A stone is whirled in a vertical circle at the end of a string. When the stone is at the highest position the tension in the string is______________?
0

A. Zero

B. Maximum

C. Less than the weight of the stone

D. Equal to the weight of the stone

647. How many days would be in a year if the distance between the earth and the sun were reduced to half of its present value (assuming circular orbit) ?
0

A. 329 days

B. 129 days

C. 365 days

D. 730 days

648. 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_____________?
0

A. f2 + f1

B. f2 f1

C. f1f2/f2+f1

D. f1f2/f1-f2

649. The number of significant figures in the length of a bar 6200mm measured by meter rod is_______________?
0

A. 3

B. 4

C. None of these

D. 2

650. If we whirl a stone at the end of a string in the vertical circle, it is likely to break when the stone is________________?
0

A. At the point where gravity is not acting

B. At any point during motion

C. At the lowest point

D. At the highest point

651. Which one of the following has the largest energy content ?
0

A. 106 photons of wavelength 200nm (UV)

B. 106 photons of wavelength 50?m (infrared)

C. 103 photons of wavelength 2 pm (?-rays)

D. 102 photons of wavelength 1nm (x-rays)

652. Hydrogen atom does not emit X-rays because _________________?
0

A. it has a single electron

B. its energy levels are too close to each other

C. its energy levels are too far apart

D. it is too small in size

653. Smaller the least count of the instrument more is the measurement________________?
0

A. Accurate and precise

B. None of these

C. Precise

D. Accurate

654. The shaft of a motor rotates at a constant angular speed of 360rev/min. Angle turned through in 1 sec in radian is________________?
0

A. 12?

B. 6?

C. 3?

D. ?

655. Select an alternative from of uncertainly principle from the following_______________?
0

A. ?E = h/m?c(1-cos?)

B. mc2 = hv

C. Any of above

D. ?E . ?t = h

656. The SI unit of force constant is identical with that of__________________?
0

A. Surface tension

B. Pressure

C. Loudness

D. Force

657. Ground state energy of the 4th orbit in a H-atom is_____________?
0

A. 3.40 eV

B. 0.85 eV

C. 1.51 eV

D. 13.60 eV

658. The uncertainty in a measurement may occur due to_______________?
0

A. Inadequate technique

B. Natural variation of the object to be measured

C. Limitation of an instrument

D. All given in A, B and C

659. A convex lens gives a virtual image only when the objects lies_________________?
0

A. between principal focus and optical center

B. at the principal focus

C. beyond 2 f

D. between principal focus and center of curvature

660. A photon is________________?
0

A. A unit of wavelength

B. A unit of energy

C. A positively charged particle

D. A quantum of electromagnetic radiation

Previous Next

Showing 641 to 660 of 857 mcqs