Category: Physics

How long does it take for salt to dissolve in hot water? 2 minute Does salt melt in water? Water lowers the melting point of salt when it dissolves in it just as salt does for water! What happens when you mix salt and water? When salt is mixed with water, the salt dissolves because […]

How can we increase the speed of motor give two ways? The speed of rotation of an electric motor can be increased by: (i) increasing the strength of the current, (ii) increasing the number of turns in the coil. What is DC motor speed? Speed of a DC Motor A = number of parallel paths. […]

What is the difference between structural and ball and stick model? A molecular formula uses chemical symbols and subscripts to indicate the exact numbers of different atoms in a molecule or compound. A structural formula indicates the bonding arrangement of the atoms in the molecule. Ball-and-stick and space-filling models show the geometric arrangement of atoms […]

Why did Germany not invade Sweden? Hitler did not invade Sweden because he did not want to waste valuable troops in Scandinavia when he had other concerns. The Swedes proved their neutrality by not letting Germany use Swedish airspace: when the Germans flew over Sweden to attack Norway, the Swedes fired back with anti-aircraft guns. […]

How do you find the buoyant force of a balloon? Buoyant Force of Balloons The formula for buoyant force is: (B) = ρ V g. ρ = Density of Fluid (We used density of the air because the balloons were afloat, not submerged) V = Displaced Volume. g = 9.8 (gravity) Density of air(ρ)= 1.225 […]

What do numbers symbolize on the speedometer? it shows is the distance your bike has covered. If the right number is in a white dial, it means that it shows the meters in 100s covered. So, if it shows 22595 with 5 being in the white dial, that means the distance covered is 2259 km […]

Why is a 1982 D penny rare? Newly found 1982-D Small date copper cent. The Mint switched over from striking copper-alloy to copper-plated zinc planchets sometime in mid-1982 as a cost saving measure – the copper-alloy planchets were too expensive to strike and the Mint was losing money. But it didn’t end there. What are […]

What is produced when aluminum reacts with hydrochloric acid? Aluminum metal reacts with hydrochloric acid to form hydrogen gas and an aluminum chloride solution. In this investigation, you will predict the mass of hydrogen gas produced by a given amount of reactants, then measure the amount, and compare them. Hydrochloric acid is an aqueous solution […]

What acetone Cannot dissolve? Many kinds of plastic do not dissolve in acetone. Polypropylene and nylon are unaffected, PTFE unsurprisingly handles it just fine as well. Two kinds of plastic that do dissolve in acetone are PVC and polystyrene. Why is nail polish soluble in acetone but not in water? Nail varnish does not dissolve […]

Why hydrogen ion does not exist? Because the bare nucleus can readily combine with other particles (electrons, atoms, and molecules), the isolated hydrogen ion can exist only in a nearly particle-free space (high vacuum) and in the gaseous state. Why are H+ ions? Loss of an electron from H atom results in H+ . ion […]