Category: Physics

Why does a rocket keep accelerating? As the rocket velocity increases, it encounters air resistance, or aerodynamic drag, which opposes the motion. Drag increases as the square of the velocity. The thrust of the rocket must be greater than the weight plus the drag for the rocket to continue accelerating. Do Newton’s laws apply in […]

What is the best time of night to stargaze? The best time to go stargazing is the days before, during and soon after each new Moon, when there is no Moon in the sky. During these times there is no bright Moon to wash out the light from fainter stars. Can you sleep in your […]

Do elements in a period share chemical properties? All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor. Arranged this way, groups of elements in the same column have similar chemical and physical properties, reflecting the […]

What makes up 80% of air? Air is composed of a mixture of gases and is not a gas in itself. However, air is mostly nitrogen — almost 80 percent of it. Nearly all the rest of it is oxygen, with about 1 percent being argon. All of the rest of the gases make up […]

How long must you boil water to make it safe to drink? Boil water, if you do not have bottled water. Boiling is sufficient to kill pathogenic bacteria, viruses and protozoa (WHO, 2015). If water is cloudy, let it settle and filter it through a clean cloth, paperboiling water towel, or coffee filter. Bring water […]

What minimum force must you exert to get the fridge to start moving? 660 newtons How is Mue calculated? It is usually symbolized by the Greek letter mu (μ). Mathematically, μ = F/N, where F is the frictional force and N is the normal force. Because both F and N are measured in units of […]

How do you tell if your hearing is damaged? 10 Signs of Hearing Loss Speech and other sounds seem muffled. Difficulty hearing high-pitched sounds (e.g., birds, doorbell, telephone, alarm clock) Difficulty understanding conversations when you are in a noisy place, such as a restaurant. Difficulty understanding speech over the phone. How long does it take […]

Why is a burette more accurate? Burettes are larger than a pipette, it has a stopcock at the bottom to control the release of liquid. Burette is similar like graduated cylinder and is easier to measure a required volume of liquid through graduations. But, it has large meniscus and hence its accuracy and precision is […]

Why the adsorption is always exothermic? The particles are attached to the surface of another medium for the reaction to take place. During this process the residual forces on the surface of adsorbent decreases which in turn decreases the surface energy. This energy appears in the form of heat, hence adsorption is exothermic in nature. […]

Which gun has the most recoil? 950 JDJ. This gun is no joke. It uses 240 grains of powder to push a 2,400-grain bullet 2,100 fps. It bites on both ends though, generating 277 foot-pounds of recoil, or approximately 10 times as much as a 30-06. What rifle kicks the hardest? Petzal: The Hardest Kicking […]