Which one of the following statements is true with regard to a greenhouse ?

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Q: 20 (CDS-I/2022)

Which one of the following statements is true with regard to a greenhouse ?

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,143,78,143,36,25,17

keywords: 

{'greenhouse': [0, 0, 0, 1], 'infrared radiations': [0, 0, 0, 3], 'infrared radiation': [0, 0, 3, 3], 'glass': [0, 0, 1, 4], 'longer wavelength': [0, 0, 1, 2], 'shorter wavelength': [0, 0, 1, 1], 'sun': [3, 0, 0, 6], 'plants': [11, 0, 4, 4]}

In a greenhouse, the glass panels act as a barrier that allows certain types of radiation to enter and exit. Option 1 states that shorter wavelength infrared radiations from the Sun can enter into the greenhouse, while longer wavelength infrared radiations from the ground and the plants inside the greenhouse cannot pass back out through the glass.

To understand this, we need to know that sunlight contains a range of wavelengths, including visible light and infrared radiation. These radiations heat up the objects they come into contact with. When the Sun`s rays enter a greenhouse, the glass allows the shorter wavelength infrared radiation to pass through. This radiation heats up the objects inside like the ground surface and plants.

However, when these objects emit longer wavelength infrared radiation as a result of being heated, the glass blocks their passage. This creates a trapping effect within the greenhouse, known as the greenhouse effect. The trapped heat warms the air and objects inside the greenhouse, creating a favorable environment for plant growth.

Option 1 accurately describes how a greenhouse operates by allowing shorter wavelength infrared radiation to enter while blocking the longer wavelength infrared radiation from escaping through the glass. The other options do not accurately describe this phenomenon.

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