Category: Physics

How much mass is lost in a fusion reaction? A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about 3.6 × 1011 kJ of energy per mole of He42 produced. How long can fusion energy […]

What causes changes in seasons? Seasons change because of the tilt of the Earth and the planet’s movement around the Sun. Did you know? It takes about 365.25 days for the Earth to orbit the Sun. We have leap years to make up for the extra ¼ day! Why are there only two seasons in […]

How do you know if a graph is direct or inverse? Numerically: Direct Variation: Because k is positive, y increases as x increases. So as x increases by 1, y increases by 1.5. Inverse Variation: Because k is positive, y decreases as x increases. Is addition and subtraction inverse relationship? Addition and subtraction are inverse […]

Which of the following best describes a sailing vessel? A sailing vessel is any vessel under sail, provided that propelling machinery, if fitted, is not being used. A vessel not under command is any vessel, which through unusual circumstances is unable to manoeuvre as required by the Collision Regulations, and so is unable to keep […]

What are the five characteristics of fungi? Characteristics of Fungi Fungi are eukaryotic organisms means they have true nucleus which are enclosed in membranes. They are non-vascular organisms. Fungi have cell walls (plants also have cell walls, but animals have no cell walls). There is no embryonic stage for fungi. They reproduce by means of […]

What are the selection rules for vibrational transitions? Thus, the selection rule for a harmonic oscillator transition is ∆v = ± 1. The physical meaning of the vibrational selection rule is this: The vibration must change the molecular dipole moment to have a non-zero (electric) transition dipole moment. Which transition between rotational energy levels is […]

How do you tell if a freezer is going out? Your Freezer is Freezing Over Your freezer is supposed to freeze your food not freeze itself. One of the most obvious signs of how to tell if your freezer is going out is when it’s so frozen that the door sticks or ice starts forming […]

Which of the following has the smallest atomic radius group of answer choices? Helium What is the trend for atomic radius down a group? In general, atomic radius decreases across a period and increases down a group. Across a period, effective nuclear charge increases as electron shielding remains constant. Why does atomic radius increase as […]

Does ice melt at 2 degrees? No ice would have melted.) To melt the ice, you must keep in mind that it takes a certain amount of energy to warm up the ice from -2 degrees to 0 degrees, and then it takes some extra energy to MELT the ice of 0 degrees to liquid […]

Is nuclear power eco friendly? Nuclear energy is considered by some as ecological energy in the sense that producing electricity with nuclear fission emits almost no CO2 or fine particles. On the contrary, coal or oil, and even gas, when put into combustion to produce electricity (or heat, or to power an engine), emit CO2 […]