Category: Physics

Should you put plastic behind insulation? Without a vapor barrier in place, condensation inside the walls could ruin the insulation and promote the growth of harmful mold and bacteria. Plastic, specifically 6-mil polyethylene plastic, is the most commonly used vapor barrier. Should you put plastic over insulation before drywall? Without poly beneath the drywall, water […]

Is the atomic number the number of electrons? The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus. In an uncharged atom, the atomic number is also equal to the number of electrons. The sum of the atomic number Z and the number of neutrons N gives […]

What is the role of carbon dioxide in photosynthesis and in cellular respiration? Photosynthesis makes the glucose that is used in cellular respiration to make ATP. While photosynthesis requires carbon dioxide and releases oxygen, cellular respiration requires oxygen and releases carbon dioxide. It is the released oxygen that is used by us and most other […]

What keeps the sun from exploding? The inward pressure that keeps a star from exploding is the gravitational attraction of the gas mantle surrounding the core (which is most of the volume of the Sun, and is very hot but does not burn itself). Why does the sun not explode like a hydrogen bomb? The […]

How long should ice be used to reduce swelling? Cold will reduce pain and swelling. Apply an ice or cold pack right away to prevent or minimize swelling. Apply the ice or cold pack for 10 to 20 minutes, 3 or more times a day. What are puffy ankles a sign of? Common causes of […]

Why is potential energy negative in an atom? When a stable atom is formed, the electron is attracted to the nucleus, r is less than infinity, and the energy will be negative. A negative value for the energy implies that energy must be supplied to the system if the electron is to overcome the attractive […]

What is full form of SI unit? Système international What is called 1 unit? A unit is any measurement that there is 1 of. So 1 meter is a unit. And 1 second is also a unit. And 1 m/s (one meter per second) is also a unit, because there is one of it. What […]

What is the most calming color to paint a bedroom? For a relaxing atmosphere in your bedroom, look to cooler hues — shades of gray, blue, green and purple — to lend a hand. These colors have been shown to reduce stress and anxiety. They can also make a space seem more expansive, so they’re […]

Can dolphins kill you? THEY may have a reputation for being friendly, cute and curious creatures, but dolphins can also be extremely vicious – and attacks on humans are on the rise. Just last month, 10-year-old Lexi Yeo was savaged by a pair of captive bottlenose dolphins, while on a swim experience in Cancun, Mexico. […]

What is the relation between charge and mass? The charge-to-mass ratio (Q/m) of an object is, as its name implies, the charge of an object divided by the mass of the same object. This quantity is generally useful only for objects that may be treated as particles. Why does oxygen need 2 electrons? Oxygen needs […]