MCQOPTIONS
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MCQOPTIONS
This section includes 2268 Mcqs, each offering curated multiple-choice questions to sharpen your Grade7 knowledge and support exam preparation. Choose a topic below to get started.
| 601. |
When a large amount of solute dissolves in a given amount of solvent it forms |
| A. | dilute solution |
| B. | saturated solution |
| C. | aqueous solution |
| D. | concentrated solution |
| Answer» E. | |
| 602. |
Some metals are so unreactive that they do not react with |
| A. | copper |
| B. | silver |
| C. | gold |
| D. | all of above |
| Answer» E. | |
| 603. |
Medicinal drugs are bitter in taste hence they are added with |
| A. | sugar |
| B. | salt |
| C. | water |
| D. | dry ice |
| Answer» B. salt | |
| 604. |
Solubility depends upon |
| A. | temperature |
| B. | solute |
| C. | solvent |
| D. | all of above |
| Answer» E. | |
| 605. |
Ships use echolocation to measure the |
| A. | size of fish |
| B. | density of water |
| C. | depth of water |
| D. | area of ocean |
| Answer» D. area of ocean | |
| 606. |
The wave with compressions and rarefactions is known as |
| A. | transverse waves |
| B. | longitudinal waves |
| C. | latitudinal waves |
| D. | horizontal waves |
| Answer» C. latitudinal waves | |
| 607. |
The exact speed of sound depends upon |
| A. | pressure |
| B. | temperature |
| C. | density |
| D. | mass |
| Answer» C. density | |
| 608. |
The medical use of ultrasound is to detect |
| A. | baby |
| B. | cancer cells |
| C. | infected parts of the body |
| D. | damaged organs |
| Answer» B. cancer cells | |
| 609. |
Long chain of atom is linked by |
| A. | hydrogen |
| B. | oxygen |
| C. | nitrogen |
| D. | carbon |
| Answer» E. | |
| 610. |
The odour of ammonia is |
| A. | sweet |
| B. | attractive |
| C. | weak |
| D. | strong and pungent |
| Answer» E. | |
| 611. |
Polythene was discovered in |
| A. | 1733 |
| B. | 1833 |
| C. | 1933 |
| D. | 1633 |
| Answer» D. 1633 | |
| 612. |
When gas is cooled down, it changes its state into liquid. This is called |
| A. | melting |
| B. | freezing |
| C. | condensation |
| D. | sublimation |
| Answer» D. sublimation | |
| 613. |
By heating the color of mixture of sulphur and iron which is yellow turns to |
| A. | black |
| B. | brown |
| C. | dark grey |
| D. | white |
| Answer» D. white | |
| 614. |
Magnetic effect is present in |
| A. | track |
| B. | train |
| C. | track and train both |
| D. | wires above the train |
| Answer» D. wires above the train | |
| 615. |
Air and water can conduct electricity only, when they contain |
| A. | electrons |
| B. | protons |
| C. | ions |
| D. | photons |
| Answer» D. photons | |
| 616. |
Most of the electric appliances get energy from |
| A. | cells |
| B. | batteries |
| C. | main supply |
| D. | dynamos |
| Answer» D. dynamos | |
| 617. |
The coil sits between the north and the south pole of the |
| A. | electromagnet |
| B. | permanent magnet |
| C. | temporary magnet |
| D. | mechanical magnet |
| Answer» C. temporary magnet | |
| 618. |
In DC motor, the coil between two carbon rods or other contacts to which electric current is fed, is called |
| A. | springs |
| B. | brushes |
| C. | mutators |
| D. | receptors |
| Answer» C. mutators | |
| 619. |
The way of collecting facts about sun is also sending satellites |
| A. | to heaven |
| B. | on sun |
| C. | to space |
| D. | to earth |
| Answer» D. to earth | |
| 620. |
The diameter of each dish of separate aerial telescope is |
| A. | 20m |
| B. | 25m |
| C. | 30m |
| D. | 35m |
| Answer» C. 30m | |
| 621. |
"Sirius-A" is a |
| A. | yellow star |
| B. | white dwarf |
| C. | blue giant |
| D. | red supergiant |
| Answer» C. blue giant | |
| 622. |
Stars produce |
| A. | light only |
| B. | heat and light |
| C. | heat, light and sound |
| D. | heat, light, sound and radiations |
| Answer» E. | |
| 623. |
A gigantic collection of stars, dust and gases held together by gravity is known as |
| A. | solar system |
| B. | galaxy |
| C. | cluster |
| D. | comet |
| Answer» C. cluster | |
| 624. |
Sound is measured by units that are called |
| A. | Hertz (Hz) |
| B. | Decibels (dB) |
| C. | Meters (m) |
| D. | Pascal (Pa) |
| Answer» C. Meters (m) | |
| 625. |
Sound waves are converted by |
| A. | speakers |
| B. | computers |
| C. | microphones |
| D. | monitors |
| Answer» D. monitors | |
| 626. |
One of the vibrations of the string makes |
| A. | pitch of the instrument |
| B. | pitch of the note |
| C. | scale of the note |
| D. | pitch of the scale |
| Answer» C. scale of the note | |
| 627. |
The caliber of instrumental note depends on the |
| A. | depth of drum |
| B. | string length |
| C. | length of wind holes |
| D. | radius of wind holes |
| Answer» B. string length | |
| 628. |
The pitch of the note depends upon the |
| A. | tension on string |
| B. | diameter of wind hole |
| C. | tension on drum surface |
| D. | diameter of drum surface |
| Answer» D. diameter of drum surface | |
| 629. |
'Eardrum' bursts at |
| A. | 40 dB |
| B. | 80 dB |
| C. | 160 dB |
| D. | 320 dB |
| Answer» D. 320 dB | |
| 630. |
20 dB has hundred times more energy than |
| A. | 10 dB |
| B. | 0 dB |
| C. | 5 dB |
| D. | 2 dB |
| Answer» C. 5 dB | |
| 631. |
An example of longitudinal wave is |
| A. | slinky spring |
| B. | light |
| C. | energy |
| D. | water wave |
| Answer» B. light | |
| 632. |
A drum makes sound of |
| A. | high frequency |
| B. | low amplitude |
| C. | high pitch |
| D. | low pitch |
| Answer» E. | |
| 633. |
Like light, sound cannot |
| A. | pass through transparent solids |
| B. | pass through air |
| C. | pass through liquids |
| D. | pass through vacuum |
| Answer» E. | |
| 634. |
X-rays are only reflected by |
| A. | soft surfaces |
| B. | thick surfaces |
| C. | thin surfaces |
| D. | hard surfaces |
| Answer» E. | |
| 635. |
Most of the sounds around world are |
| A. | artificial |
| B. | natural |
| C. | man made |
| D. | made electronically |
| Answer» C. man made | |
| 636. |
Some fishing boats use echo to |
| A. | calculate the depth of water |
| B. | detect any predator |
| C. | detect shoal of fish |
| D. | eggs of fish |
| Answer» D. eggs of fish | |
| 637. |
Sound can travel through air because |
| A. | air has pressure |
| B. | air has humidity |
| C. | air has particles |
| D. | air has temperature |
| Answer» D. air has temperature | |
| 638. |
A strong beam of ultrasound can melt even a |
| A. | glass |
| B. | metal |
| C. | soap |
| D. | wax |
| Answer» C. soap | |
| 639. |
The distance between two points of a wave in a phase is known as |
| A. | wave front |
| B. | frequency |
| C. | amplitude |
| D. | wavelength |
| Answer» E. | |
| 640. |
Sounds are chiefly produced by |
| A. | friction |
| B. | energy |
| C. | vibration |
| D. | disturbance |
| Answer» D. disturbance | |
| 641. |
The microphone changes the sound waves into |
| A. | mechanical signals |
| B. | electrical signals |
| C. | light signals |
| D. | wave signals |
| Answer» C. light signals | |
| 642. |
The speed of sound in glass is |
| A. | 2000 m/s |
| B. | 6000 m/s |
| C. | 10000 m/s |
| D. | 14000 m/s |
| Answer» C. 10000 m/s | |
| 643. |
One example of string instrument is |
| A. | piano |
| B. | drum |
| C. | saxophone |
| D. | trombone |
| Answer» B. drum | |
| 644. |
Long exposure to sounds is dangerous for |
| A. | ears |
| B. | brain |
| C. | nerves |
| D. | eyes |
| Answer» B. brain | |
| 645. |
The sequence of notes is known as |
| A. | plain |
| B. | scale |
| C. | balance |
| D. | proportion |
| Answer» C. balance | |
| 646. |
String instruments produce sound when |
| A. | string is pushed |
| B. | string is pulled |
| C. | string is banged |
| D. | string lift up |
| Answer» B. string is pulled | |
| 647. |
Repetition of sound in empty hall is known as |
| A. | echo |
| B. | harsh echo |
| C. | hollow echo |
| D. | soft echo |
| Answer» B. harsh echo | |
| 648. |
The term "vibration" has been derived from Latin word |
| A. | loqui |
| B. | vibrationem |
| C. | silentium |
| D. | biennium |
| Answer» C. silentium | |
| 649. |
In air, change in pressure produces |
| A. | sound waves |
| B. | vibrations |
| C. | light waves |
| D. | thermal energy |
| Answer» B. vibrations | |
| 650. |
An animal that can hear sounds with low frequency than human ear is |
| A. | whale |
| B. | pigeon |
| C. | snake |
| D. | dog |
| Answer» E. | |