Have you ever noticed that when you are in a car, or a bus, travelling on a straight road, the Sun appears to move right along with you? While telephone poles and trees close to the road, whiz past in the blink of an eye, the Sun is always visible throughout the journey. No matter how fast Daddy drives, you …
Read More »Why does the sky look blue from the earth and black from the moon?
A phenomenon called Rayleigh’s Scattering causes light to scatter when it passes through particles that have a diameter one-tenth that of the wavelength (colour) of light. Sunlight is made up of different colours, but because of the elements in the atmosphere, the colour blue is scattered more efficiently than other colours making the sky appear blue. However, the moon does …
Read More »Why does the moon appear upside down in the southern hemisphere?
The moon orbits near the equator of the Earth. In the southern hemisphere, we are standing at the opposite side of the globe, from a person who is standing in the northern hemisphere. So, we are literally standing upside down with relation to the person at the other end. We, therefore, see the moon from a completely different vantage point. …
Read More »Why does the jasmine bloom only at night?
Like all other flowering plants, jasmine also produces a flower inducing hormone in its leaves when exposed to bright sunlight. This hormone is called florigen (flower-generating hormone) and it migrates from the leaves to flowering shoots during the day. It accumulates in the flowering shoots of the jasmine plant and induces flowering during the night.
Read More »Why does the black box remain intact in an air crash?
Each aircraft is fitted with two pieces of equipment – Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) – that are designed to survive an air crash so that the data recorded helps investigators reconstruct events preceding the crash. FDR records values of about 700 parameters related to the flight and controls and CVR records conversations taking place in …
Read More »Why does steel glow when it’s hot?
Hot steel glows red when hot because its atoms vibrate with a lot of energy. The amount of energy varies in atoms resulting in a range of colours.
Read More »Padmini
Padmini born and raised in Thiruvananthapuram in what was then the princely state of Travancore (now the Indian state of Kerela), Padmini was the second daughter of Thankappan Pillai and Sarawathi Amma. Her sisters, Lalitha and Ragini, were also renowned film actresses. Together, the threesome were known as the Travancore sisters. Padmini had her early education at Mahila Mandiram School …
Read More »Why does snow look white but water is colorless?
Snow is a block of individual ice crystals arranged together. When a light photon enters a layer of snow, it goes through an ice crystal on the top, which changes its direction slightly and sends it on to a new ice crystal, which does the same thing. Basically, all the crystals bounce the light all around, so that it comes …
Read More »Why does it hurt our eyes to look at snow on a sunny day?
On a sunny day the bright sunlight bounces off the white snow, making the light even brighter. It usually takes a while for our eyes to become comfortable when we look at something as bright as that. People often wear sunglasses when they go skiing or go to the beach to protect their eyes from the strong light.
Read More »Why does iron go red when heated?
Iron goes red when heated because its atoms radiate vibratory waves of an electrodynamics nature which are visible as light at a sufficiently high temperature. At 800 Centigrade the iron is at low-red heat. But as the heat increases the iron will turn bright red, and finally white hot and molten. Heat is passed through the iron by conduction the …
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