In terms of SI unit that prefixes $10^{- 15}$ is called_____.

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Important Points to Remember

In Physics, we study a large number of physical quantities, which can be broadly classified into two categories: scalars and vectors.

(i) Vector Quantities are the physical quantities, which have magnitude and direction both, e.g., Displacement, velocity, acceleration, force, momentum, torque, etc. For a quantity to be a vector, it is necessary that it follows the triangle rule of addition of two vectors.

(ii) Scalar Quantities Physical quantities which have magnitude only. e.g. Mass, speed, volume, work, time, power, energy, etc. are scalar quantities.

Newton's Laws of Motion:

(i) First Law states that every body maintains its initial state of rest or uniform motion on a straight line unless an external force acts on it.

(ii) Second Law states that the forces acting on an object is directly proportional to the product of the mass of the object and the acceleration produced on it.

(iii) Third Law states that to every action, there is an equal and opposite reaction.
Energy:

(i) The capacity for doing work by a body is called its energy.

(ii) Energy is a scalar quantity and its unit is the joule.

(iii) There are two types of mechanical energy: Kinetic Energy (K) is the energy possessed by a body due to its motion and Potential Energy (U) is the capacity of doing work developed in a body due to its position or configuration.
Work:
Work is said to be done if force acting on a body is able to actually move it through some distance in the direction of the force. Its SI unit is the joule. Work = FS cos q.
Power:
Rate of doing work is called power. Its unit is the watt. Power = Work done/ Time taken.
Gravitation:
Everybody in the universe attracts other body by a force called the force of gravitation. The gravitational force of the earth is called gravity. The acceleration produced in a body due to force of gravity is called acceleration due to gravity (g), and its value is 9.8 meter per second sq.
Satellites:
Satellites are natural or artificial bodies revolving around a planet under its gravitational force of attraction. Moon is a natural satellite, while INSAT-B is an artificial satellite of Earth.
General Properties of Matter:
Pressure:

(i) Pressure is defined as a force acting normally on a unit area of the surface. Pressure= Force/Area

(ii) Elasticity is the property of the material of a body by virtue of which the body acquires its original shape and size after the removal of deforming force.

(iii) Archimedes’ Principle states that a body is immersed partly or wholly in a liquid, there is an apparent loss in the weight of the body, which is equal to the weight of the liquid displaced by the body.

(iv) Elasticity is the property of the material of a body by virtue of which the body acquires its original shape and size after the removal of deforming force.

(v) The phenomenon of rising or depression of liquids in a capillary tube is called capillarity.

(vi) Viscosity is the property of a fluid by virtue of which an internal frictional force acts between its layers when it is in motion.

(vii) Density is defined as mass per unit volume. Relative density is measured by hydrometer.

(viii) The property of a liquid by virtue of which it tries to minimise its free surface area is called the surface tension.

(ix) Bernoulli’s Theorem states when an incompressible and non-viscous liquid (or gas) flows in streamlined motion from one place to another, then at every point of its path the total energy per unit volume (pressure energy + kinetic energy + potential energy) is constant.
Heat and Thermodynamics:

(i) Heat is a form of energy, which measures the sensation or perception of warmness or coldness of a body or environment.

(ii) Temperature is the measurement of hotness or coldness of a body.

(iii) The amount of heat required to raise the temperature of a unit mass of a substance through 1°C, is called its specific heat.

(iv) Thermal expansion is the increase in size on heating. A solid can undergo three types of expansions (a) Linear expansion (b) Superficial expansion (c) Cubical expansion.

(v) Evaporation is the slow process of conversion of liquid into its vapour even below its boiling.

(vi) Latent Heat is the heat energy absorbed or released at constant temperature per unit mass for change of state.

(vii) The Transfer of heat from one place to other place is called transmission of heat, like conduction in solids, convection in liquids, and radiation in space.

(viii) A simple pendulum is a heavy point mass suspended from rigid support by means of an elastic and inextensible string. The time period of a simple pendulum does not depend upon the mass, shape and size of the bob and its amplitude of oscillation.
Waves:

(i) A wave is a disturbance, which propagates energy from one place to the other without the transportation of matter. They are of two types (a) Mechanical wave (longitudinal wave and transverse wave) (b) Electromagnetic wave.

(ii) Sound Waves are longitudinal mechanical waves. Categories. The sound waves which lie in the frequency range 20 Hz to 20000 Hz are called audible waves.

(iii) SONAR, Pitch, Echo are the terms associated with the sound.
Light:

(i) Light is a form of energy, which is propagated as an electromagnetic wave. It is the form of energy. It is a transverse wave.

(ii) Laws of Reflection: the incident ray, reflected ray and the normal to the reflecting surface at the incident point all lie in the same plane. The angle of reflection is equal to the angle of incidence.

(iii) When a ray of light falls on a boundary separating two media comes back into the same medium, then this phenomenon is called reflection of light.

(iv) The bending of the ray of light passing from one medium to other medium is called refraction.

(v) Spherical mirrors are of two types; (i) Concave mirror (ii) Convex mirror. The image formed by a convex mirror is always virtual, erect and diminished.

(vi) Optical Fibre works on the principle of TIR. It is used for telecommunication and various medical purposes like endoscopy.

(vii) When a ray of white light is passed through a prism, it gets split into its constituent colours. This phenomenon is called the dispersion of light.

(viii) The lens is generally of two types (i) Convex lens (ii) Concave lens

(ix) When the lens is dipped in a liquid of higher refractive index, the focal length increases and convex lens behave as a concave lens and vice-versa.
Electricity and Magnetism:

(i) The charge is the basic property associated with the matter due to which it produces and experiences electric and magnetic effects.

(ii) Electric current is defined as the rate of flow of charge or charge flowing per unit time. Its unit is ampere.
Ohm’s Law:
At the constant physical conditions of any conductor, the current flowing through the conductor is directly proportional to the potential difference across it.
Magnets:
Magnet is a piece of iron or other materials that can attract iron-containing object and points toward the North when suspended.
Atomic and Nuclear Physics:

(i) Cathode ray was discovered by Sir William Crooke and its properties are: Rays travel in straight lines and produce fluorescence.

(ii) Canal Rays were discovered by Goldstein. It consists of positively charged particles.

(iii) X-rays are electromagnetic waves with a wavelength range of 0.1 Å−100 Å. X-rays were discovered by Roentgen.

(iv) Radioactivity was discovered by Henry Becquerel, Madame Curie and Pierre Curie for which they jointly won Nobel Prize.

(v) The nuclear reaction, in which a heavy nucleus splits into two nuclei of Nearly equal mass is nuclear fission.

(vi) When two or more light nuclei combined together to form a heavier nucleus is called nuclear fusion.

(vii) The nuclear reactor is an arrangement, in which controlled nuclear fission reaction takes place.

(viii) Laser: (Light Amplification by Stimulated Emission of Radiation) It is a device that produces an intense, coherent and highly directional beam of the single frequency. It can be transmitted over a great distance without being spread.