1489 + Mcqs in Science Page 28 McqOptions

1351.	In which of the three media does sound travel the fastest?
A.	Air
B.	Water
C.	Steel
D.	Speed is same in any medium
Answer» D. Speed is same in any medium

Discussion

1352.	A person can be identified by his voice. What determines this distinguishing feature? (i) Amplitude (ii) Pitch (iii) Loudness
A.	Only (i)
B.	Only (ii) and (iii)
C.	Only (i) and (iii)
D.	(i), (ii) and (iii)
Answer» B. Only (ii) and (iii)

Discussion

1353.	How can the brain interpret the frequency of a sound?
A.	By the loudness of sound
B.	By the frequency of sound
C.	By the pitch of sound
D.	By the amplitude of sound
Answer» D. By the amplitude of sound

Discussion

1354.	Which of the following correctly describes the pitch and the frequency of the sound of a girl's scream?
A.	Low pitch, low frequency
B.	Low pitch, high frequency
C.	High pitch, low frequency
D.	High pitch, high frequency
Answer» E.

Discussion

1355.	A student sets up a slinky PQ on a smooth table top in the manner as shown in figure. How can he produce transverse waves in the slinky by moving its free end Q?
A.	At an angle of \[45{}^\circ \] with the table top
B.	Backward and forward along the length of the slinky
C.	Up and down
D.	Left and right
Answer» E.

Discussion

1356.	The picture shows a xylophone. A, B, C and D are the rods in it. Which of the following rods has high pitch of the sound and which has low frequency of vibrations?
A.	High pitch Low frequency D A
B.	High pitch Low frequency B and C B and C
C.	High pitch Low frequency A and D A and D
D.	High pitch Low frequency A D
Answer» E.

Discussion

1357.	What is the number of vibrations made by a body in one second called?
A.	Frequency
B.	Wavelength
C.	Loudness
D.	Pitch
Answer» B. Wavelength

Discussion

1358.	Identify the three delicate bones in the middle ear.
A.	Pinna, anvil and cochlea
B.	Hammer, anvil and cochlea
C.	Pinna, eardrum and anvil
D.	Hammer, anvil and stirrup
Answer» E.

Discussion

1359.	A student performed an experiment as shown in the figure.What would be happened as air was pumped out of the jar and the electric bell rang?
A.	The sound became louder.
B.	The sound became fainter first and then louder once all the air was pumped out.
C.	The sound could not be heard anymore.
D.	The sound was the same as before.
Answer» D. The sound was the same as before.

Discussion

1360.	In an experiment to measure the speed of sound in air, a boy stands 40 m away from a wall and bangs two pieces of wood together. At the instant he hears the echo, he bangs them together again. He does this activity 50 times. The time taken for 50 bangs is 12 s. Which calculation gives the speed of sound in air?
A.	\[\frac{12}{40\times 50}\]
B.	\[\frac{40\times 50}{12}\]
C.	\[\frac{40\times 2\times 50}{12}\]
D.	\[\frac{40\times 2\times 12}{50}\]
Answer» D. \[\frac{40\times 2\times 12}{50}\]

Discussion

1361.	If the temperature increases, then what happens to the frequency of the sound produced by the organ pipe?
A.	Increases
B.	Decreases
C.	Unchanged
D.	Can't say
Answer» B. Decreases

Discussion

1362.	Time taken for 10 oscillation of a body is 20 second, then time period of the body is
A.	1 sec
B.	2 sec
C.	3 sec
D.	4 sec
Answer» E.

Discussion

1363.	An object moving at a speed greater than that of sound is said to be moving at
A.	ultrasonic speed
B.	sonic speed
C.	infrasonic speed
D.	supersonic speed
Answer» E.

Discussion

1364.	Unit of loudness
A.	Hertz (Hz)
B.	meter
C.	second
D.	none of these
Answer» E.

Discussion

1365.	Shrill sound is of
A.	higher frequency
B.	lower frequency
C.	higher amplitude
D.	lower amplitude
Answer» B. lower frequency

Discussion

1366.	The sound in human is produced by
A.	heart
B.	mouth
C.	larynx
D.	hair
Answer» D. hair

Discussion

1367.	A man stands in between two cliffs and explodes a cracker. He hears the first echo after 0.6s and the second echo after 2.4s. Calculate the distance between the cliffs, (speed of sound = 336 m/s)
A.	515 m
B.	520 m
C.	504 m
D.	505 m
Answer» D. 505 m

Discussion

1368.	The speed of sound is 330 m/s and that of light is \[^{3X}{{10}^{8}}m/s\] . The ratio of speed of sound to light is approximately
A.	\[1={{10}^{5}}\]
B.	\[1={{10}^{6}}\]
C.	\[1={{10}^{6}}\]
D.	\[1={{10}^{7}}\]
Answer» C. \[1={{10}^{6}}\]

Discussion

1369.	A man stands in between two cliffs and fires a gun. He hears two successive echoes after 3 seconds and 5 seconds. What is the distance between two cliffs? [speed of sound\[=\text{ }330m{{s}^{-1}}\]]
A.	1320 m
B.	132 m
C.	1333 m
D.	1230 m
Answer» B. 132 m

Discussion

1370.	The instrument used in the laboratory to produce sound of fixed frequency is ____
A.	Simple pendulum
B.	Tuning fork
C.	Thermometer
D.	Meter scale
Answer» C. Thermometer

Discussion

1371.	Meradona was standing on the cliff, 825 m from the point, from where the gun was fired. After how long he will hear the echo? Speed of sound is taken as 330 m/s.
A.	1 sec
B.	2 sec
C.	4 sec
D.	5 sec
Answer» E.

Discussion

1372.	What happens when a glass rod is rubbed with silk cloth?
A.	Electrons are added to it.
B.	Electrons are removed from it.
C.	Protons are added to it.
D.	Protons are removed from it.
Answer» C. Protons are added to it.

Discussion

1373.	Two electroscope one positively charged (X) and the other negatively charged (Y) are connected with a copper wire as shown in figure. Which of the following will happen?
A.	Electrons will move from X to Y.
B.	Protons will move from X to Y.
C.	Electrons will move from Y to X.
D.	Protons will move from Y to X.
Answer» D. Protons will move from Y to X.

Discussion

1374.	Consider the following statements and select the correct option which correctly identifies true (T) and false (F).(i) A charged object can attract something that is neutral.(ii) An atom that gains electrons becomes positively charged.(iii) Charges are only transferred from one body to another.
A.	(i)(ii)(iii)TFT
B.	(i)(ii)(iii)FTF
C.	(i)(ii)(iii)FFT
D.	(i)(ii)(iii)TTF
Answer» B. (i)(ii)(iii)FTF

Discussion

1375.	Which of the following is/are affected during lightning?
A.	TV.
B.	Radio
C.	Telephone
D.	All of the above
Answer» E.

Discussion

1376.	What are the weak zones that are present around the boundaries of plates underneath the earth and cause slides and earthquakes commonly known as?
A.	Fault zones
B.	Eruption zones
C.	Explosive zones
D.	Sliding zones
Answer» B. Eruption zones

Discussion

1377.	What are high speed winds accompanied with?
A.	Increased pressure
B.	Reduced pressure
C.	Water vapour
D.	Static electricity
Answer» C. Water vapour

Discussion

1378.	When we remove polyester or woollen cloth in dark, we can see spark and hear a cracking sound. These are due to
A.	Static electricity
B.	Current electricity
C.	Reflection of light
D.	Refraction of light.
Answer» B. Current electricity

Discussion

1379.	Which of these things would you do if you live in the earthquake prone area? (i) You would always keep an emergency kit ready. (ii) You would have only open book shelves and open cupboards in your house. (iii) You would fix the cupboards to the walls. (iv) You would not keep breakable items on the upper shelves.
A.	Only (iii) is correct.
B.	Both (i) and (ii) are correct.
C.	(i), (iii) and (iv) are correct.
D.	All are correct.
Answer» D. All are correct.

Discussion

1380.	Which of the following plays an important role in the early-warning systems for cyclones?
A.	Helicopters
B.	Submarines
C.	Satellites
D.	Stars
Answer» D. Stars

Discussion

1381.	What is the nature of electrical charges generated by rubbing two objects?
A.	Static
B.	Mobile
C.	Positive
D.	Negative
Answer» B. Mobile

Discussion

1382.	What is the force present between two charged bodies called?
A.	Electrostatic force
B.	Electromagnetic force
C.	Gravitational force
D.	Frictional force
Answer» B. Electromagnetic force

Discussion

1383.	The instrument which is used to measure and record the magnitude of an earthquake in terms of shockwaves is known as:
A.	(a) Ritcher scale
B.	(b) Electroscope
C.	(c) Seismograph
D.	(d) All of these
Answer» D. (d) All of these

Discussion

1384.	If an object is rubbed with another object, the object which gains electrons:
A.	(a) Becomes negatively charged
B.	(b) Becomes positively charged
C.	(c) Remains neutral
D.	(d) All of these
Answer» B. (b) Becomes positively charged

Discussion

1385.	A man having blood group O married a women with blood group B and they have a girl child after one year. The blood group of the girl child will be:
A.	O
B.	B
C.	BO
D.	Equally likely
Answer» E.

Discussion

1386.	Which of the following is/are paired structure in human reproductive system?
A.	Ovary
B.	Testes
C.	Fallopian tube
D.	All of these
Answer» E.

Discussion

1387.	Which of the following is a specialized structure that provides nourishment to the foetus from the mother and collects wastes from it, passing them onto the mother?
A.	Fallopian tube
B.	Placenta
C.	Cowper's gland
D.	Blastocyst
Answer» C. Cowper's gland

Discussion

1388.	In which of the following processes is ovum released from the follicle?
A.	Ovulation
B.	Oogenesis
C.	Capacitation
D.	Menstrual cycle
Answer» B. Oogenesis

Discussion

1389.	In which of the following animals fertilization is external?
A.	Birds and fish
B.	Amphibians and birds
C.	Reptiles and fish
D.	Fish and amphians
Answer» E.

Discussion

1390.	Which of the following comparisons are true of sexual and asexual reproduction? Sexual reproduction Asexual reproduction (i) Involves two individuals Involves only one individual parent (ii) Involves a simple process Involves a complex process (iii) Involves the union of two types of gametes No fusion of gametes
A.	Only (i) and (ii)
B.	Only (i) and (iii)
C.	Only (ii) and (iii)
D.	All the above
Answer» C. Only (ii) and (iii)

Discussion

1391.	The given figure represents the location of various endocrine glands in human body.Identify the glands marked as P, Q, R, S and T and select the incorrect statement regarding these.
A.	Gland P secretes the hormone thyroxine, which regulates growth and metabolism.
B.	Gland Q secretes the hormones corticosteroids and adrenaline, which regulate breathing, heart rate, carbohydrate metabolism and mineral balance.
C.	Glands S and T secrete the hormones which control secondary sexual characters in females and males respectively.
D.	Gland R secretes the hormone insulin, whose increased concentration leads to diabetes.
Answer» E.

Discussion

1392.	Consider the following statements and select the option which correctly identifies true (T) and false (F) ones.(i) Reproductive life of woman lasts from menarche to menopause.(ii) In females, the uterus wall thickens to receive the embryo.(iii) Estrogen is released by testes at the onset of puberty.(iv) Hormones secreted by adrenal glands stimulate testes and ovaries to produce their hormones.
A.	(i)(ii)(iii)(iv)TFTF
B.	(i)(ii)(iii)(iv)TFFF
C.	(i)(ii)(iii)(iv)TTFF
D.	(i)(ii)(iii)(iv)TTFT
Answer» D. (i)(ii)(iii)(iv)TTFT

Discussion

1393.	Thyroxine controls ____ in frogs and the development of ___ during embryonic development of other vertebrates. Thyroxine production requires the presence of ____ in diet.Select the correct sequence of words to complete the above passage.
A.	Development, Circulatory system, Iodine
B.	Metamorphosis, Circulatory system, Calcium
C.	Development, Nervous system, Iron
D.	Metamorphosis, Nervous system, Iodine
Answer» E.

Discussion

1394.	Which of the following organisms undergo metamorphosis? (i) Silk moth (ii) Snake (iii) Frog (iv) Hen (v) Butterfly (vi) Human (vii) Cat (viii) Cockroach (ix) Whale (x) Dog
A.	(i), (ii), (iii), (v) and (x) only
B.	(i), (iii), (v) and (viii) only
C.	(ii), (iii), (iv) and (v) only
D.	(iv), (vi), (vii) and (ix) only
Answer» C. (ii), (iii), (iv) and (v) only

Discussion

1395.	Which of the following statements is incorrect regarding the female reproductive system?
A.	If the ovum released from the ovaries is not fertilised, then it is shed along with blood during menstruation.
B.	Menopause occurs in the females at an age of 45-50 years.
C.	Vagina of female reproductive system is a primary sex organ.
D.	Development of breasts in females is the accessory sex character.
Answer» D. Development of breasts in females is the accessory sex character.

Discussion

1396.	Which of the following is correct about the part labelled X?
A.	It gives protection to the penis.
B.	It is a structure that produces sperms.
C.	It is a narrow duct that acts as a passage for urine only.
D.	It is a narrow duct that acts as a passage for both urine and sperms.
Answer» E.

Discussion

1397.	Deficiency of which hormone causes goitre?
A.	Adrenaline
B.	Thyroxine
C.	Insulin
D.	Testosterone
Answer» C. Insulin

Discussion

1398.	_____ hormone is also known as emergency hormone.
A.	Growth
B.	Adrenaline
C.	Aldosterone
D.	Insulin
Answer» C. Aldosterone

Discussion

1399.	The first occurrence of monthly period at puberty is called:
A.	Menstruation
B.	Menopause
C.	Menarche
D.	Metamorphosis
Answer» D. Metamorphosis

Discussion

1400.	Chemical substances which co-ordinate the activities of living organisms and their growth?
A.	Endocrine glands
B.	Nutrition
C.	Hormones
D.	Chromosomes
Answer» D. Chromosomes

Discussion

Explore topic-wise MCQs in 8th Class.

In which of the three media does sound travel the fastest?

A person can be identified by his voice. What determines this distinguishing feature? (i) Amplitude (ii) Pitch (iii) Loudness

How can the brain interpret the frequency of a sound?

Which of the following correctly describes the pitch and the frequency of the sound of a girl's scream?

A student sets up a slinky PQ on a smooth table top in the manner as shown in figure. How can he produce transverse waves in the slinky by moving its free end Q?

The picture shows a xylophone. A, B, C and D are the rods in it. Which of the following rods has high pitch of the sound and which has low frequency of vibrations?

What is the number of vibrations made by a body in one second called?

Identify the three delicate bones in the middle ear.

A student performed an experiment as shown in the figure.What would be happened as air was pumped out of the jar and the electric bell rang?

If the temperature increases, then what happens to the frequency of the sound produced by the organ pipe?

Time taken for 10 oscillation of a body is 20 second, then time period of the body is

An object moving at a speed greater than that of sound is said to be moving at

Unit of loudness

Shrill sound is of

The sound in human is produced by

A man stands in between two cliffs and explodes a cracker. He hears the first echo after 0.6s and the second echo after 2.4s. Calculate the distance between the cliffs, (speed of sound = 336 m/s)

The speed of sound is 330 m/s and that of light is \[^{3X}{{10}^{8}}m/s\] . The ratio of speed of sound to light is approximately

A man stands in between two cliffs and fires a gun. He hears two successive echoes after 3 seconds and 5 seconds. What is the distance between two cliffs? [speed of sound\[=\text{ }330m{{s}^{-1}}\]]

The instrument used in the laboratory to produce sound of fixed frequency is ____

Meradona was standing on the cliff, 825 m from the point, from where the gun was fired. After how long he will hear the echo? Speed of sound is taken as 330 m/s.

What happens when a glass rod is rubbed with silk cloth?

Two electroscope one positively charged (X) and the other negatively charged (Y) are connected with a copper wire as shown in figure. Which of the following will happen?

Consider the following statements and select the correct option which correctly identifies true (T) and false (F).(i) A charged object can attract something that is neutral.(ii) An atom that gains electrons becomes positively charged.(iii) Charges are only transferred from one body to another.

Which of the following is/are affected during lightning?

What are the weak zones that are present around the boundaries of plates underneath the earth and cause slides and earthquakes commonly known as?

What are high speed winds accompanied with?

When we remove polyester or woollen cloth in dark, we can see spark and hear a cracking sound. These are due to

Which of the following plays an important role in the early-warning systems for cyclones?

What is the nature of electrical charges generated by rubbing two objects?

What is the force present between two charged bodies called?

The instrument which is used to measure and record the magnitude of an earthquake in terms of shockwaves is known as:

If an object is rubbed with another object, the object which gains electrons:

A man having blood group O married a women with blood group B and they have a girl child after one year. The blood group of the girl child will be:

Which of the following is/are paired structure in human reproductive system?

Which of the following is a specialized structure that provides nourishment to the foetus from the mother and collects wastes from it, passing them onto the mother?

In which of the following processes is ovum released from the follicle?

In which of the following animals fertilization is external?

The given figure represents the location of various endocrine glands in human body.Identify the glands marked as P, Q, R, S and T and select the incorrect statement regarding these.

Thyroxine controls ____ in frogs and the development of ___ during embryonic development of other vertebrates. Thyroxine production requires the presence of ____ in diet.Select the correct sequence of words to complete the above passage.

Which of the following organisms undergo metamorphosis? (i) Silk moth (ii) Snake (iii) Frog (iv) Hen (v) Butterfly (vi) Human (vii) Cat (viii) Cockroach (ix) Whale (x) Dog

Which of the following statements is incorrect regarding the female reproductive system?

Which of the following is correct about the part labelled X?

Deficiency of which hormone causes goitre?

_____ hormone is also known as emergency hormone.

The first occurrence of monthly period at puberty is called:

Chemical substances which co-ordinate the activities of living organisms and their growth?

Thyroxine controls __ in frogs and the development of _ during embryonic development of other vertebrates. Thyroxine production requires the presence of ____ in diet.Select the correct sequence of words to complete the above passage.