Physics definitions Name of quantity Definitions Unit 1 Physical quantity SI unit Volume Mass Density Scalar Vector Speed Velocity Distance Displacement Linear motion Non-linear motion Acceleration Deceleration Force Weight Normal contact force Tension force Resisting forces Friction force Drag force Up thrust force Newton 1st law Driving force (D) Resisting force (R) Centripetal force Deformation Elastic deformation Plastic deformation Hooke’s law Moment Center of mass Law of conservation of momentum Impulse Atmospheric pressure Barometer Manometer Energy Any quantity that can be measured Main units that all other units are derived from It’s the space occupied by the object Amount of a matter in a body Mass per unit volume Any quantity which has magnitude only (speed, distance, volume) Any quantity which has magnitude and direction (velocity, force) Distance per unit time Displacement per unit time Actual path covered by the object Shortest path from start to end Moving in a straight line Circular motion Rate of increase in velocity per unit time Rate of decrease in velocity per unit time It’s a push or a pull on a body It’s a gravitational pull on a body / attractive gravitational force It’s a reaction force from the surface due to the object resting on it/ perpendicular to the surface It’s a force when pulling a rope Forces opposite to the motion of the object Force between any two moving objects in contact with each other Resisting force inside a fluid An upward force exerted on an object fully/partially submerged in a fluid A body will stay at rest or in a constant velocity unless a resultant force acted on it Force in direction of motion Force opposite to direction of motion It’s the inward resultant force directed towards the center of the circle It’s change in shape or length due to applied force It’s returning back to original shape after removing the applied force It’s not returning back to original shape after removing the applied force Force and extension are directly proportional until reaching elastic limit or limit of proportionality Quantity that measures the turning effect of a force around a pivot Point in the body where the whole weight is considered to act Total momentum before collision = total momentum after collision Change in momentum (mv-mu) Or Force * time Pressure caused due to molecules of the atmosphere Measures the atmospheric pressure Measures the difference in pressure between two gases Ability of the body to do work Physics definitions Law of conservation of energy Electric energy Chemical energy Heat energy Elastic / strain energy Potential energy Kinetic energy Work done Renewable resources Non-renewable resources Nuclear fusion Nuclear fission Power Energy can’t Be created nor destroyed it can only be changed from one form to another Energy gained by charges as they flow through electric supply Energy stored in the bonds of chemical compounds Energy transferred due to difference in temperature Energy gained by a body when experience bending /twisting/compression/stretching Energy stored inside a body due to its position Energy gained due to motion of the body Energy gained by an object due to an external force moving the object a certain distance Sources of energy that don’t run out and can be replaced Sources of energy that can run out and cannot be replaced Joining of two small nuclei producing on large nucleus Splitting of one large nucleus into two smaller nuclei Rate of energy transfer Unit 2 Temperature Evaporation Heating Brownian motion Cooling Pressure Sensitivity Range Linearity Response time Specific heat capacity Heat capacity Specific latent heat Specific latent heat of fusion Specific latent heat of vaporization Boiling point The measure of the average kinetic energy possessed by each molecule of the substance It’s a change in state form liquid to gas at any temperature occur by escaping of most energetic molecules on the surface causing cooling effect Heat is absorbed by the matter A zigzag random motion of solid particles suspended in a fluid Heat is released by the matter Force per unit area Amount of increase in volume corresponding to a change in temperature Range of temperatures the thermometer could measure Difference between maximum and minimum temperatures Increase in volume directly proportional to the rise in temperature Time taken by the thermometer to be thermal equilibrium with the body Amount of heat energy needed to raise the temperature of 1 Kg of a body by 1°C Amount of heat energy needed to raise the temperature of the whole body by 1°C Amount of heat energy needed to change the state of 1 kg of a body Amount of heat energy needed to change the state of 1 kg of a body from solid to liquid Amount of heat energy needed to change the state of 1 kg of a body from liquid to gas Temperature at which liquid boils and changes state to gas Unit 3 Wave Mechanical wave Electromagnetic wave Longitudinal waves Compression It’s a way of energy transmission due to vibration of particles Waves that need a medium to travel, so they can’t travel through a vacuum (space) Waves that don’t need a medium to travel, so they are able to travel through a vacuum (space) Waves where the particles vibrate left and right parallel to energy motion, and these waves contain regions of compressions and rarefactions A region where spacing between molecules is low and pressure is high Physics definitions Rarefaction Transverse waves Amplitude Wavelength Period time Wave front Normal line Angle of incidence Angle of reflection Diffraction Echo Refraction Total internal reflection Optical fiber Refractive index Dispersion of light Mono chromatic Point F Point C Principle axis Principle focus Focal length A region where spacing between molecules is high and pressure is low Waves where the particles vibrate up and down perpendicular to energy motion, they do not contain compressions and rarefactions Maximum displacement from mean position Distance between 2 successive crests or troughs, or compressions / rarefactions Time taken by the wave to make 1 complete cycle Points on same crest and trough Virtual line drawn perpendicular to the surface at the point where incident ray hit the surface Angle between incident ray and normal line Angle between reflected ray and normal line Spreading of wave due to a barrier Reflection of sound waves Change in speed due to change in medium Means that incident angle is greater than critical angle Very thin solid tube made of glass or plastic Ratio to compare properties of light in air and vacuum with any other medium Separation of white light into seven spectrum colors Light that contain one wavelength or color or frequency The optical center of the lens Point at the center of the lens Line passing through the optical center and perpendicular to lens surface Point on the principle axis where the rays meet after being refracted by the lens Distance between principle focus and center of lens q Unit 4 Conductors Insulators Electrostatic force Electric field Current Electromotive force (e.m.f) Potential difference (p.d) Electromagnetic Induction Galvanometer Thermistor LDR (Light dependent resistor ) LED(Light emitting diode) Relay Materials that contain free moving electrons and allow flow of charges through them Materials that don’t contain free moving electrons and don’t allow flow of charges through them Force done by charges where like charges repel, and opposite charges attract Region around charge where any other enter this region it will experience electrostatic force (attraction/ repulsion) Rate of flow of charges / Charges per unit time Amount of energy gained by one charge when passing through the battery Amount of energy lost by one charge when passing through a device It’s a phenomena in which e.m.f is induced in a wire as it cuts magnetic field perpendicularly It’s a device which measures the current and volt at same time A resistor that changes its resistance when temperature changes (Temperature = Resistance ) A resistor that changes its resistance when light intensity changes (Light intensity = Resistance ) It’s a regular lamp but lights up in high voltage only It’s a small circuit which drives large circuit Physics definitions Analogue devices Digital devices A device in which voltage can have any value A device in which voltage can only have 2 values (0 or 1) Unit 5 Isotopes Gamma Radiation Ionization GM-tube Background radiation Half life These are atom of the same element with the same proton number but different number of neutrons It’s an electromagnetic wave can travel through vacuum Means losing electron and become +ve Or gaining electron and become –ve Device which counts the amount of radiations, but is not able to tell the type of radiation it receiving It’s random radiation due to surroundings or natural sources Time taken for the radiation emitted by the source to decrease to its half Unit 6 Accretion Accretion disc Planets Dwarf planets Ellipse Eccentricity Asteroids and meteoroids Comets Equator Solar mass Solar system Galaxy Universe The addition of matter to each other due to the influence of gravity A flat rotating disc of matter formed due to the accretion process Spherical structures in the solar system that orbit the sun, no two planets can be in the same orbit Spherical objects not large enough to be considered a planet that orbit the sun A squashed circle A measure of how much the orbit is elliptical Rocky objects that orbit the sun An object made of ice, gas and dust that orbits the sun in a highly elliptical orbit Imaginary line drawn around the earth halfway between the north pole and the south pole It’s the mass of a sun and it is used to compare with the masses of other stars, e.g if a star has 8 solar masses, then it is 8 times more massive than our sun A star and a collection of planets and moons A large collection of billions of stars Space and all the galaxies in it
