General Science Physics MCQ-3

Which of the following electromagnetic waves has the longest wavelength?

(A) Infrared rays
(B) Gamma rays
(C) Light rays
(D) Ultraviolet rays

If v1 ,v2 and v3 are the velocities of sound in steel, water and vacuum respectively. Which one of the following relations is correct?

(A) v1=v2=v3
(B) v123
(C) v12v
(D) v1v2 + v3

Consider the following statements
1. The boiling point of a liquid increases on increasing the pressure on the free surface of the liquid.
2. On heating the solid substance if the volume of the substance increases, then by the application of pressure its melting point increases.
Which of the statement(s) given above is/are correct?

(A) 1 and 2
(B) Only 1
(C) Only 2
(D) Neither 1 nor 2

If temperature rises, the coefficient of viscosity of liquid

(A) increases
(B) decreases
(C) remains unchanged
(D) None of the above

X-rays are not used for radar purpose because

(A) they are completely absorbed by air
(B) they are not reflected by the target
(C) they are not electromagnetic wave
(D) None of the above

A source of sound waves towards an observer

(A) The wavelength of sound in the medium towards the observer is decreased
(B) The frequency of the source is increased
(C) The velocity of the sound in the medium is increased
(D) The amplitude of vibration of the particles is increased

Consider the following statements
1. The liquid pressure is inversely proportional to the density of liquid.
2. The pressure exerted on the liquid doesn’t depend upon the shape or size of the container.
Which of the statement(s) given above is/are correct?

(A) Only 1
(B) Only 2
(C) Both 1 and 2
(D) Neither 1 nor 2

Bernoulli’s theorem is applicable to

(A) surface tension
(B) viscosity
(C) flow of liquids
(D) static fluid pressure

X-rays were discovered by

(A) Roentgen
(B) Becquerel
(C) Curie
(D) Van lane

The velocity of sound produced by a vibrating body varies

(A) Inversely as the frequency of the medium
(B) Inversely as the density of the medium
(C) Directly as the square root of density of the medium
(D) Directly as the square root of frequency of the medium

The operating principle of a hydraulic press is

(A) Boyle’s law
(B) Pascal’s principle
(C) Archimedes’ principle
(D) Newton’s law of gravitation

When the terminal velocity is reached, the acceleration of a body moving through a viscous medium is

(A) negative
(B) positive
(C) zero
(D) None of the above

Which one of the following is not electromagnetic in nature?

(A) Cathode rays
(B) X-rays
(C) Gamma rays
(D) Infrared rays

X-rays are heavily absorbed by lead atoms, but to obtain X-rays photograph of stomach barium sulphate is usually given to the patient instead of lead salt, because

(A) Lead salts given fainter image
(B) Lead salts are more poisonous
(C) Barium salts reflect less
(D) Barium salts give brighter image

An iron piece and a wooden piece have equal weights in air. If they are removed from air to vacuum

(A) the wooden piece appears to weight more
(B) the iron piece appears to weight more
(C) there is no change in the weight of either
(D) None of the above

An application of Bernoulli’s equation for fluid flows is found in

(A) viscosity meter
(B) capillary rise
(C) hydraulic press
(D) dynamic lift of an aero plane

Consider the following parts of spectra
1. Visible
2. Infrared
3. Ultraviolet
Which one of the following is the correct sequence in which their wavelengths increase?

(A) 4-3-1-2
(B) 4-1-2-3
(C) 3-2-1-4
(D) 3-1-2-4