4to40.com

Is it possible for all planets in our solar system to align in a straight line?

Theoretically, no, as the plane of orbit of each planet is tilted slightly in relation to other planets. However, if we ignore the intra-orbital plane tilt, then the chance of all planets (eight now excluding Pluto) to be at the right ascension with respect to sun at same time would be once in 180 trillion years. For an exact alignment, …

Read More »

Is an octopus dangerous to man?

There are stories of people being attacked by an octopus and frantically tying to detach the suckers of the encircling arms. This may happen very rarely and when it does the octopus is really investigating a new moving shape rather than attacking it. If the person could manage to keep perfectly still the octopus would soon let him go.

Read More »

If the density of gold is more than that of iron, why is gold softer than iron?

The softness of a metal is its ability to undergo permanent deformation under applied stress. All metals have specific crystalline structures. Each structure has its own densely packed crystalline planes. There exist line defects and plane defects in a crystal system. Such defects are more in densely packed crystal systems, i.e., metallic crystals with higher density, and result in a …

Read More »

If noble gases are supposed to be inert and unreactive, how is krypton difluoride formed?

While krypton is generally an inert element, in extreme volatile conditions, it can form compounds in very small quantities. There are several ways that krypton can form its fluoride: by passing through an electrical arc, proton bombardment or photochemical process. All these processes require a very heavy amount of energy. Krypton has achieved a unique importance in science. In 1960, …

Read More »

If leaves get their colour from chlorophyll, what gives flowers their colour?

Plant cells have cell organelles known as plastids, which are colouring agents. There are three types of plastids – chloroplasts (contain green pigment chlorophyll), leucoplasts (white or colourless plastids) and chromoplasts (contain other pigments). All cells have varying proportions of these. Flowers have a majority of the third type and get their colours from these. From Wikipedia Chromoplasts are plastids …

Read More »