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On a given tennis court, the distance between the base line and the net is 10 m and the distance between the service line and the net is 5 m. The net is 0.9 m high. A player serves the ball directly above the base line. (Assume the ball travels in a straight line.) What is the m..

Since Haber's process proceeds with a decrease in volume, it is favored by high pressure. In actual practice, a pressure of 200 - 900 atmospheres is employe..

Find the average percentage raise of salary if a person receives 25% raise after 1 year of service and 15% raise after the second year of service. => 19.36% or 1.199% or 19.9% or 20%..

Nitrogen readily combines with highly electropositive metals (Group 1), even at room temperature, to give nitrides. For example,..

Metals have high tensile strength. Metals can resist stretching without breaking. A strong electrostatic attraction between the positively charged kernels and the mobile electrons surrounding them is the reason for tensile strengt..

For high fidelity reception, the audio frequencies from 20Hz to 20000Hz must be reproduced. This requires a bandwidth + 20000Hz i.e., 40000Hz. (Note that both the sidebands must be reproduced). The bandwidth actually assigned for AM transmission is 20000Hz. This is done to keep the inter..

In this process, coal is heated in the absence of air to about 1273 - 1473 K. The major products of high temperature pyrolysis are, Coal..

Electron affinity is the amount of energy released, when an isolated gaseous atom accepts an electron to form a negative ion. The other atom participating in the formation of an ionic compound must form an anion by gaining an electron (s). Higher electron affinity favours the formation of an anion..

Welcome to the brave new world of high-tech dentistry. Here, teeth stained by coffee, tea and tobacco are bleached considerably white in a single sitting, and crowned and laminated in a single visit. Infected gum tissue can be vaporized bloodlessly in a few minutes with lasers. Even thou..

Elements that have higher ionisation energies cannot form ionic bonds, as they cannot lose electrons easily. Instead, they acquire stability by mutual sharing of electrons, and therefore form covalent bond..