Which device raises or lowers alternating voltage through electromagnetic induction?
Correct answer: D
A transformer uses coupled coils and changing magnetic flux.
Science
✓ 0
✗ 0
Your Result
0 correct out of 0 attempted (0%)
Which phenomenon splits white light into its component colours in a prism?
Correct answer: B
Different wavelengths refract by different amounts.
Which SI unit measures electrical resistance?
Correct answer: D
Resistance relates potential difference to current.
Which heat-transfer process can occur through a vacuum?
Correct answer: D
Thermal radiation does not need a material medium.
Which quantity remains unchanged when light enters glass from air?
Correct answer: D
The wavelength and speed change while frequency remains constant.
Which SI unit measures potential difference?
Correct answer: B
Potential difference is energy transferred per unit charge.
Which SI unit measures electric current?
Correct answer: A
Current is the rate of flow of electric charge.
Which SI unit measures force?
Correct answer: B
A newton equals kg·m/s².
Which SI unit measures frequency?
Correct answer: C
One hertz means one cycle per second.
Which SI unit measures energy?
Correct answer: B
Work and energy share the unit joule.
Evaluate the two proposed answers. Which are supported? I. An ambulance siren changing pitch as it passes — the physical principle illustrated: Refraction. II. A rocket accelerating by ejecting gas — the physical principle illustrated: Conservation of momentum.
Correct answer: A
I is incorrect: An ambulance siren changing pitch as it passes → Doppler effect. Relative motion changes the frequency heard by the observer. II is correct: A rocket accelerating by ejecting gas → Conservation of momentum. Gas and rocket gain oppositely directed momentum.
For A sharp knife cutting more easily than a blunt one, identify the physical principle illustrated.
Correct answer: C
For a given force, pressure equals force divided by area.
Evaluate the two proposed answers. Which are supported? I. A ship floating despite being made of steel — the physical principle illustrated: Pressure increases when contact area falls. II. A sound becoming higher pitched — the physical principle illustrated: Refraction through air layers.
Correct answer: A
I is incorrect: A ship floating despite being made of steel → Buoyancy. Displaced water can provide an upthrust equal to the ship's weight. II is incorrect: A sound becoming higher pitched → Increase in frequency. Pitch depends mainly on vibration frequency.
Evaluate the two proposed answers. Which are supported? I. Water cooling an earthen pot — the physical principle illustrated: Evaporative cooling. II. An optical fibre guiding light — the physical principle illustrated: Total internal reflection.
Correct answer: C
I is correct: Water cooling an earthen pot → Evaporative cooling. Escaping water molecules carry away energy. II is correct: An optical fibre guiding light → Total internal reflection. Light can be confined within a higher-index core.
For A black surface warming strongly in sunlight, identify the physical principle illustrated.
Correct answer: A
Dark matte surfaces are generally effective absorbers.
Evaluate the two proposed answers. Which are supported? I. A refrigerator transferring heat from its cold interior — the physical principle illustrated: Work-driven heat transfer. II. An ambulance siren changing pitch as it passes — the physical principle illustrated: Doppler effect.
Correct answer: D
I is correct: A refrigerator transferring heat from its cold interior → Work-driven heat transfer. External work allows heat to move from colder to warmer surroundings. II is correct: An ambulance siren changing pitch as it passes → Doppler effect. Relative motion changes the frequency heard by the observer.
For A passenger lurching forward when a bus stops, identify the physical principle illustrated.
Correct answer: B
The body tends to retain its previous state of motion.
Evaluate the two proposed answers. Which are supported? I. A sharp knife cutting more easily than a blunt one — the physical principle illustrated: Pressure increases when contact area falls. II. A sound becoming higher pitched — the physical principle illustrated: Refraction through air layers.
Correct answer: C
I is correct: A sharp knife cutting more easily than a blunt one → Pressure increases when contact area falls. For a given force, pressure equals force divided by area. II is incorrect: A sound becoming higher pitched → Increase in frequency. Pitch depends mainly on vibration frequency.
Evaluate the two proposed answers. Which are supported? I. A fuse melting under excess current — the physical principle illustrated: Greater absorption of radiation. II. A ship floating despite being made of steel — the physical principle illustrated: Increase in frequency.
Correct answer: A
I is incorrect: A fuse melting under excess current → Heating effect of current. Joule heating raises the fuse element's temperature. II is incorrect: A ship floating despite being made of steel → Buoyancy. Displaced water can provide an upthrust equal to the ship's weight.
For A spoon appearing bent in water, identify the physical principle illustrated.
Correct answer: C
Light changes direction between media of different optical density.
Evaluate the two proposed answers. Which are supported? I. A rocket accelerating by ejecting gas — the physical principle illustrated: Buoyancy. II. A refrigerator transferring heat from its cold interior — the physical principle illustrated: Work-driven heat transfer.
Correct answer: D
I is incorrect: A rocket accelerating by ejecting gas → Conservation of momentum. Gas and rocket gain oppositely directed momentum. II is correct: A refrigerator transferring heat from its cold interior → Work-driven heat transfer. External work allows heat to move from colder to warmer surroundings.
For An ambulance siren changing pitch as it passes, identify the physical principle illustrated.
Correct answer: B
Relative motion changes the frequency heard by the observer.
Evaluate the two proposed answers. Which are supported? I. A hydraulic lift multiplying force — the physical principle illustrated: Pressure increases when contact area falls. II. A ship floating despite being made of steel — the physical principle illustrated: Pressure increases when contact area falls.
Correct answer: D
I is incorrect: A hydraulic lift multiplying force → Pascal's law. Pressure applied to confined fluid is transmitted throughout it. II is incorrect: A ship floating despite being made of steel → Buoyancy. Displaced water can provide an upthrust equal to the ship's weight.
For A fuse melting under excess current, identify the physical principle illustrated.
Correct answer: C
Joule heating raises the fuse element's temperature.
Evaluate the two proposed answers. Which are supported? I. A sound becoming higher pitched — the physical principle illustrated: Refraction. II. A mirage above hot ground — the physical principle illustrated: Refraction through air layers.
Correct answer: B
I is incorrect: A sound becoming higher pitched → Increase in frequency. Pitch depends mainly on vibration frequency. II is correct: A mirage above hot ground → Refraction through air layers. A temperature gradient changes air's refractive index.