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  • Why smoking makes people look old?

  • So that we look more experienced and intelligent!

  • Naahhh!

  • Smoking makes people look old because things like cigarettes contain nicotine.

  • Nicotine is a vasoconstrictor, which means it narrows our blood vessels, restricting the blood supply.

  • When the blood supply is restricted, our cells don't get the required oxygen and nutrients.

  • As a result, our skin becomes dry and discoloured.

  • In addition to this, the collagen and elastin fibers, which keep our skin firm and elastic, begin to break down much faster, leading to saggy and wrinkled skin.

  • Also, when we smoke, we purse our lips and squint our eyes.

  • Regularly repeating these actions may also cause wrinkles on our lips and around our eyes.

  • In this way, smoking makes our skin dry, saggy and wrinkled, thus making us look old.

  • Why is snow white?

  • 'Cause it applies fairness cream!

  • No!

  • Sunlight or white light is a combination of all visible colors of light.

  • When light falls on an object, it may absorb some colors of light and reflect the remaining colors.

  • The colors which are reflected by an object make up its color.

  • For example, when light falls on an apple, it absorbs all other colors except red.

  • Apple reflects red color, making it appear red.

  • When light falls on coal, it absorbs all colors and does not reflect any color.

  • Hence, coal appears black to us.

  • Really?

  • I didn't know that!

  • Now, snow does not absorb any colors of light and reflects all of them equally.

  • As the combination of all colors of light is white light, snow appears white to us.

  • Topic: Anaerobic Respiration

  • What is the cause of muscle cramps?

  • Excess sleep!

  • Nooo!

  • Respiration is a process in which the cells of our body produce energy.

  • Normally, our cells respire aerobically.

  • In this process, the glucose, with the help of oxygen, is completely broken down to produce energy, water and carbon dioxide.

  • Is this energy then used for all our activities?

  • Indeed!

  • However, during heavy exercise, our body cannot deliver enough oxygen to the cells of our muscles.

  • Hence, in such situations, anaerobic respiration helps us to produce some energy temporarily and thus continue our work.

  • In anaerobic respiration, the glucose is partially broken down in the absence of oxygen to produce comparatively less amount of energy.

  • And a waste product called lactic acid.

  • Now, one of the most prominent reasons for the muscle cramps is the accumulation of this lactic acid.

  • Topic: Sublimation

  • Why do mothballs disappear over time?

  • Wow!

  • You have a nice collection of clothes!

  • But have you kept mothballs to protect them?

  • Yeah, yeah!

  • I had kept them a few months back below these clothes!

  • Hey!

  • Where did the mothballs go?

  • I placed them right here!

  • Did you steal them?

  • No, no!

  • I haven't stolen anything!

  • Mothballs disappear over time.

  • Do you know why?

  • It is because of a process called sublimation.

  • During sublimation, a solid on heating, converts directly into vapor without passing through the intermediate liquid state.

  • Don't lie!

  • How is that even possible?

  • See, I also hid a burger here many days ago!

  • It did not disappear!

  • Oh, gross!

  • Just throw that burger in the dustbin!

  • Not all substances sublimate.

  • Mothballs are made up of naphthalene.

  • Naphthalene has very weak intermolecular forces.

  • Because of these weak forces, the mothball, which is made up of naphthalene, sublimates.

  • That is, it changes its state from solid to vapor.

  • Now, this vapor is either absorbed by the fabric or it escapes into the atmosphere, causing the mothballs to disappear over time.

Why smoking makes people look old?

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