Category: Physics

What level of radiation is harmful? To cause death within hours of exposure to radiation, the dose needs to be very high, 10Gy or higher, while 4-5Gy will kill within 60 days, and less than 1.5-2Gy will not be lethal in the short term. However all doses, no matter how small, carry a finite risk […]

What is the equation for total energy? Equations Equation Meaning in words E m = K + U E_\text m = K +U Em=K+U The total mechanical energy of a system is the sum of the total kinetic energy and total potential energy. How do you calculate time? To solve for time use the formula […]

Can humans see light speed? Yes. We can see the objects moving at speed of light. But we do not have that technology yet and we do not know if anything with mass can travel at speed of light. One can see objects if photons can reach his eyes even if he is travelling at […]

Are greenhouse gases good or bad? The greenhouse effect is a good thing. It warms the planet to its comfortable average of 59 degrees Fahrenheit (15 degrees Celsius) and keeps life on earth, well, livable. Without it the world would be a frozen, uninhabitable place, more like Mars. Why is greenhouse gas bad? Greenhouse gases […]

What are the 3 real primary colors? Color Basics Three Primary Colors (Ps): Red, Yellow, Blue. Three Secondary Colors (S’): Orange, Green, Violet. Six Tertiary Colors (Ts): Red-Orange, Yellow-Orange, Yellow-Green, Blue-Green, Blue-Violet, Red-Violet, which are formed by mixing a primary with a secondary. Does Google have a new logo? Google is replacing its iconic Gmail […]

Which layer is closest to space? Layers of Earth’s Atmosphere exosphere—contains few particles that move into and from space. exobase—the lower boundary of the exosphere. thermosphere—temperature increases with height. The International Space Station orbits Earth in this layer. mesopause—the boundary between the mesosphere and the thermosphere; the coldest place on Earth. What layer are satellites? […]

When you have a plane determined by 3 points how do you calculate the normal vector? In summary, if you are given three points, you can take the cross product of the vectors between two pairs of points to determine a normal vector n. Pick one of the three points, and let a be the […]

What is a magnetic field how can the direction? the magnetic fields are the imaginary line which moves from south to north. this lines do not overlap each other. we can find the direction of the magnetic field lines by keeping a compass near to it. Why do 2 magnets repel or attract each other? […]

What are the disadvantages of resistance training? ISOMETRIC ISOTONIC Disadvantages: angle specific limited use in sports limited strength and endurance gains cannot monitor intensity large increases in blood pressure higher injury risk (free weights, uncontrolled movement) expensive weight lifted is limited by the ‘sticking point’ more muscle soreness Should I do resistance training everyday? One […]

Which type of stars are the youngest? Yellow dwarfs are small, main sequence stars. The Sun is a yellow dwarf. A red dwarf is a small, cool, very faint, main sequence star whose surface temperature is under about 4,000 K. Red dwarfs are the most common type of star…. TYPE Star IV Subgiants V Main […]