
UPTET 2019 Exam Important Science Questions:
Q1.Human ear responds to intensities in range
मानव कान कितनी सीमा तक तीव्रता का जवाब देता है

Q2.Sound waves are produced by
ध्वनि तरंगें किस के द्वारा निर्मित होती हैं?
(a) Linear motion/ रेखीय गति
(b) Circular motion/ घूर्नन गति
(c) Vibrating bodies/ शरीर के कंपन
(d) Transitional motion/ संक्रमणकालीन गति
Q3. Loudness of sound varies directly with vibrating bodies
ध्वनि की प्रबलता कंपन शरीर के साथ सीधे बदलती है-
(a) Intensity/ तीव्रता
(b) Amplitude/ आयाम
(c) Pitch/ पिच
(d) Quality/ गुणवत्ता
Q4.Sensation of sound persists in our brain for about
ध्वनि का संवेग हमारे मस्तिष्क में लगभग कितने समय तक रहता है
(a) 0.001s
(b) 0.2s
(c) 0.1s
(d) 10s
Q5.Sound energy passing per second through a unit area held perpendicular is called
लंबवत एक इकाई क्षेत्र के माध्यम से प्रति सेकंड ध्वनि ऊर्जा पारित होती है उसे क्या कहा जाता है?
(a) Intensity/ तीव्रता
(b) Frequency/ आवृत्ति
(c) Amplitude/ आयाम
(d) Quality/ गुणवत्ता
Q6. Which one of the following is used for determining the structure of crystal?
क्रिस्टल की संरचना का निर्धारण करने के लिए निम्नलिखित में से किसका उपयोग किया जाता है:
(a) Gamma rays / गामा किरणें
(b) X-rays / एक्स-रे
(c) UV rays / यूवी किरणें
(d) Visible light / दृश्य प्रकाश
Q7.Speed of sound in solids is
ठोस में ध्वनि की गति है
(a) 10 times that in gas/ गैस से 10 गुणा
(b) 20 times that in gas/गैस से 20 गुणा
(c) 5 times that in gas/गैस से 5 गुणा
(d) 15 times that in gas/गैस से 15 गुणा
Q8. Which waves cannot be transmitted through vacuum?
वैक्यूम के माध्यम से कौन सी तरंगों को प्रेषित नहीं किया जा सकता है?
(a) Light / प्रकाश
(b) Heat / ऊष्मा
(c) Sound / ध्वनि
(d) Electromagnetic / विद्युत चुम्बकीय
Q9.Speed of sound in air depends on the
हवा में ध्वनि की गति किस पर निर्भर करती है?
(a) Chemical conditions/ रासायनिक स्थिति
(b) Physical conditions/ भौतिक स्थिति
(c) Pitch/ पिच
(d) None of these/इनमें से कोई नहीं
Q10.Sound waves can be transmitted by any
ध्वनि तरंगों को किसी भी _________ द्वारा प्रेषित किया जा सकता है
(a) Medium/ मीडियम
(b) Vacuum/ शून्यक
(c) Both medium and vacuum/ मीडियम और शून्यक दोनों
(d) None of the above/इनमें से कोई नहीं

S2.Ans(c)
Sol. Sound is produced when something vibrates. The vibrating body causes the medium (water, air, etc.) around it to vibrate.
S3.Ans(b)
Sol. Loudness of Sound: Loudness of sound depends on amplitude of vibration. Loudness of sound is directly proportional to square of amplitude of vibration.
S4.Ans(c)
Sol. The sensation of hearing of any sound persists in our brain for 0.1s.This is called the persistence of hearing.
S5.Ans(a)
Sol. Sound energy passes through a unit area held perpendicular to the direction of propagation of sound waves is called intensity of sound.
S6Ans.(b)
Sol. Crystallography is the science that examines crystals which can be found everywhere in nature, from salt to snowflakes to gemstones. Crystallographers use the properties of the inner structure of crystals to determine the arrangement of atoms and generate knowledge which is used by chemist, physicists and other. Crystallographers use X-ray, neutron, and electron diffraction techniques to identify the characteristics of solid materials.
S7.Ans(d)
Sol. Sound travels at 343 m/s in air; it travels at 1,480 m/s in water (4.3 times as fast as in air); and at 5,120 m/s in iron (about 15 times as fast as in air).
S8.Ans.(c)
Sol. Sound waves cannot be transmitted through vacuum. It is transmitted by the movement of particles along with the direction of the motion of the sound wave. More generally, sound is a mechanical disturbance which is dependent upon a medium to travel. It can be transmitted through solids, liquids, and gases.
S9.Ans(b)
Sol. Wind can increase or decrease the speed, and can even push sound waves sideways. Air density affects it. Temperature, pressure, humidity and gas mixture can each affect the density. So Speed of sound in air depends on the Physical conditions.
S10.Ans.(a)
Sol. Sound is transmitted through gases, plasma, and liquids as longitudinal waves, also called compression waves. It requires a medium to propagate.