Physics Questions & Answers

Physics Questions & Answers Absolute 0 - Kelvin Scale - CORRECT ANSWER- Absolute 0 - atoms have as little kinetic energy as possible Absolute 0 = -273°C 50 Kelvin = -223°C 15°C = 288 Kelvin Acceleration = - CORRECT ANSWER- Change in Velocity / Time Taken Artificial Earth Satellites - CORRECT ANSWER- Have orbital period of 1 day = geostationary satellites, used for communications Average Speed = - CORRECT ANSWER- distance / time Conduction - CORRECT ANSWER- Process where vibrating particles pass on their kinetic energy Convection - CORRECT ANSWER- Particles from their hotter region to the cooler region and take their heat energy with them Dangers of Gamma - CORRECT ANSWER- Cell mutation and Tissue damage - can cause cancer Dangers of Infra-Red - CORRECT ANSWER- Skin Burns - Heating effect Dangers of Microwaves - CORRECT ANSWER- Yeah human body tissue internally Dangers of Ultraviolet - CORRECT ANSWER- Damage surface cells and causes blindness Density = - CORRECT ANSWER- Mass / Volume Effects of gravity on planets - CORRECT ANSWER- Closer you get to a star or a planet the stronger the force of attraction is, so they move quicker in orbit Efficiency = - CORRECT ANSWER- Useful Energy Output / Total Energy Input Electromagnetic Waves - CORRECT ANSWER- Waves have different wavelengths - continuous spectrum