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The speed of light in a vacuum is approximately:- a)300,000 km/s
- b)150,000 km/s
- c)1,080,000 km/h
- d)600,000 km/h
Correct answer is option 'A'. Can you explain this answer?
The speed of light in a vacuum is approximately:
a)
300,000 km/s
b)
150,000 km/s
c)
1,080,000 km/h
d)
600,000 km/h
|
Daniel Oluwaseyi answered |
The speed of light in a vacuum is approximately 300,000 km/s. This is a fundamental constant of nature and is denoted by the symbol "c". It plays a crucial role in the theory of relativity and has many important applications in physics and engineering.
Explanation:
- The speed of light in a vacuum is an absolute constant and does not depend on the motion of the source or observer. It is the maximum speed at which information or energy can be transmitted through space.
- The value of the speed of light in a vacuum is approximately 299,792,458 meters per second, which is equivalent to 299,792.458 kilometers per second.
- The value of 300,000 km/s is often used as an approximation for the speed of light in a vacuum, as it is easier to remember and work with in calculations.
- The exact value of the speed of light in a vacuum was determined through experimental measurements and is considered one of the most accurately known physical constants.
- The speed of light in a vacuum is significantly faster than the speeds we encounter in everyday life. For example, the speed of sound in air is approximately 343 meters per second, which is much slower than the speed of light.
- The speed of light in a vacuum is constant for all observers, regardless of their relative motion. This is one of the fundamental principles of the theory of relativity.
- The speed of light in a vacuum is often used as a conversion factor between units of distance and time. For example, light from the Sun takes approximately 8 minutes and 20 seconds to reach Earth, which corresponds to a distance of about 150 million kilometers.
In conclusion, the speed of light in a vacuum is approximately 300,000 km/s. This value is an essential constant in physics and has many important applications in various fields of science and technology.
Explanation:
- The speed of light in a vacuum is an absolute constant and does not depend on the motion of the source or observer. It is the maximum speed at which information or energy can be transmitted through space.
- The value of the speed of light in a vacuum is approximately 299,792,458 meters per second, which is equivalent to 299,792.458 kilometers per second.
- The value of 300,000 km/s is often used as an approximation for the speed of light in a vacuum, as it is easier to remember and work with in calculations.
- The exact value of the speed of light in a vacuum was determined through experimental measurements and is considered one of the most accurately known physical constants.
- The speed of light in a vacuum is significantly faster than the speeds we encounter in everyday life. For example, the speed of sound in air is approximately 343 meters per second, which is much slower than the speed of light.
- The speed of light in a vacuum is constant for all observers, regardless of their relative motion. This is one of the fundamental principles of the theory of relativity.
- The speed of light in a vacuum is often used as a conversion factor between units of distance and time. For example, light from the Sun takes approximately 8 minutes and 20 seconds to reach Earth, which corresponds to a distance of about 150 million kilometers.
In conclusion, the speed of light in a vacuum is approximately 300,000 km/s. This value is an essential constant in physics and has many important applications in various fields of science and technology.
The principle of operation of a pin-hole camera is based on:- a)Reflection
- b)Refraction
- c)Interference
- d)Diffraction
Correct answer is option 'D'. Can you explain this answer?
The principle of operation of a pin-hole camera is based on:
a)
Reflection
b)
Refraction
c)
Interference
d)
Diffraction
|
|
Deepak Iyer answered |
A pin-hole camera works based on the principle of diffraction. When light passes through a small hole (pin-hole), it diffracts, forming an inverted image on the opposite side of the camera.
When a light source is blocked by an opaque object, a ______ is formed.- a)Reflection
- b)Refraction
- c)Shadow
- d)Diffraction
Correct answer is option 'C'. Can you explain this answer?
When a light source is blocked by an opaque object, a ______ is formed.
a)
Reflection
b)
Refraction
c)
Shadow
d)
Diffraction
|
|
Deepak Iyer answered |
When light is blocked by an opaque object, it prevents the light from reaching a surface or area, creating a shadow. Reflection occurs when light bounces off a surface, refraction involves the bending of light when it passes through different mediums, and diffraction refers to the bending or spreading out of light waves around obstacles.
Which of the following is a natural source of light?- a)Candle
- b)Electric bulb
- c)Sun
- d)Laser
Correct answer is option 'C'. Can you explain this answer?
Which of the following is a natural source of light?
a)
Candle
b)
Electric bulb
c)
Sun
d)
Laser
|
|
Deepak Iyer answered |
The sun is a natural source of light as it emits light and heat due to nuclear fusion reactions happening within it. Candles and electric bulbs are artificial sources of light, and lasers produce highly focused beams of light.
The frequency of light is measured in:- a)Meters
- b)Hertz
- c)Watts
- d)Kelvin
Correct answer is option 'B'. Can you explain this answer?
The frequency of light is measured in:
a)
Meters
b)
Hertz
c)
Watts
d)
Kelvin
|
|
Deepak Iyer answered |
The frequency of light refers to the number of complete cycles or oscillations of the electromagnetic wave per unit of time. It is measured in hertz (Hz), which represents the number of cycles per second.
An object that does not emit light but can be seen because it reflects light is called:- a)Luminous object
- b)Non-luminous object
- c)Transparent object
- d)Opaque object
Correct answer is option 'D'. Can you explain this answer?
An object that does not emit light but can be seen because it reflects light is called:
a)
Luminous object
b)
Non-luminous object
c)
Transparent object
d)
Opaque object
|
|
Deepak Iyer answered |
An opaque object does not emit light on its own but can be seen because it reflects light that falls upon it. Examples of opaque objects include wood, metal, and most everyday objects.
An object that emits light is called:- a)Luminous object
- b)Non-luminous object
- c)Transparent object
- d)Opaque object
Correct answer is option 'A'. Can you explain this answer?
An object that emits light is called:
a)
Luminous object
b)
Non-luminous object
c)
Transparent object
d)
Opaque object
|
|
Deepak Iyer answered |
A luminous object is one that produces and emits its own light, such as the sun, a burning candle, or a glowing light bulb. Non-luminous objects do not produce light on their own but can reflect or transmit light.
During a lunar eclipse, the Earth is between the:- a)Sun and the Moon
- b)Moon and the Sun
- c)Moon and the Earth's atmosphere
- d)Earth and the Moon's atmosphere
Correct answer is option 'A'. Can you explain this answer?
During a lunar eclipse, the Earth is between the:
a)
Sun and the Moon
b)
Moon and the Sun
c)
Moon and the Earth's atmosphere
d)
Earth and the Moon's atmosphere
|
|
Deepak Iyer answered |
During a lunar eclipse, the Earth comes between the Sun and the Moon, blocking the direct sunlight from reaching the Moon. This causes the Moon to appear dark or reddish in color during a total lunar eclipse.
In a pin-hole camera, if the distance between the object and the pin-hole is doubled, what happens to the size of the image formed?- a)Doubles
- b)Halves
- c)Remains the same
- d)Quadruples
Correct answer is option 'C'. Can you explain this answer?
In a pin-hole camera, if the distance between the object and the pin-hole is doubled, what happens to the size of the image formed?
a)
Doubles
b)
Halves
c)
Remains the same
d)
Quadruples
|
|
Deepak Iyer answered |
In a pin-hole camera, the size of the image formed remains the same regardless of the distance between the object and the pin-hole. However, the sharpness or clarity of the image may be affected by the distance.
The wavelength of light is measured in:- a)Meters
- b)Hertz
- c)Watts
- d)Kelvin
Correct answer is option 'A'. Can you explain this answer?
The wavelength of light is measured in:
a)
Meters
b)
Hertz
c)
Watts
d)
Kelvin
|
|
Deepak Iyer answered |
The wavelength of light refers to the distance between two consecutive points on a wave, such as from crest to crest or from trough to trough. It is typically measured in meters or its subunits, such as nanometers (nm) or micrometers (µm).
Chapter doubts & questions for Light Energy - Physics for JAMB 2025 is part of JAMB exam preparation. The chapters have been prepared according to the JAMB exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for JAMB 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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