Chapter 1:Introduction To Physics

Chapter 2: Forces and Motion

Definition

Definition

Physical Quantities QUANTITIES that are measurable Base quantities PHYSICAL QUANTITIES that cannot be defined in terms of other

physicalquantities but has its own definition Derived quantities PHYSICAL QUANTITIES that are derived from base quantities by

multiplication ordivision or both Scientific notation/standard

form POWERS of the base number 10 to show a very large or small number

Prefixes GROUP OF LETTERS placed at the beginning of a word to modify its

meaning,which act as multipliers Scalar quantity QUANTITY which has only magnitude or size(time, temperature, mass,

volume, distance, density, power) Vector quantity QUANTITY which has both magnitude or size and direction(force, velocity,

displacement, acceleration, momentum) Error DIFFERENCE between actual value of a quantity and the value obtained

inmeasurement Systematic errors CUMULATIVE ERRORS that can be corrected, if the errors are known.(zero

error, incorrect calibration of measuring instrument) Random errors ERRORS that arise from unknown and unpredictable variations in condition,

andwill produce a different error every time. Random errors are caused by

factorsthat are beyond the control of observers.(human limitations, lack of

sensitivity, natural errors, wrong technique) Zero error ERROR that arises when the measuring instrument does not start from

exactly zero Parallax error ERROR in reading an instrument because the observer’s eyes and the pointer

arenot in a line perpendicular to the plane of scale Measurement PROCESS of determining value of a quantity using a scientific instrument

with astandard scale Consistency ABILITY to register the same reading when a measurement is

repeated(improve – eliminates parallax error, greater care, not detective

instrument) Accuracy DEGREE to which a measurement represents the actual value(improve –

repeat readings, avoid parallax/zero error, high accuracy instrument) Sensitivity ABILITY to detect quickly a small change in the value of a

measurement(thermometer – thin wall bulb, narrow capillary) Inferences EARLY CONCLUSION that you draw from an observation or event

usinginformation that you already have on it Hypothesis GENERAL STATEMENT that is assumed to be true regarding the

relationshipbetween the manipulated variable and responding variable

Distance The distance traveled by an object is the total length that is traveled by

that object. Displacement Displacement of an object from a point of reference, O is the shortest

distance of the object from point O in a specific direction.

Speed The rate of change in distance

Velocity RATE OF CHANGE of displacement

Mass MEASURE of an object’s inertia

AMOUNT of matter in the object Acceleration RATE OF CHANGE of velocity

Inertia PROPERTY of matter that causes it to resist any change in its motion or

state of rest Momentum PRODUCT of mass and velocity Force pulling or a pushing ACTION on an object Impulsive force LARGE FORCE which acts over a very short time interval

RATE OF CHANGE in momentum Gravity FORCE originated from centre of the Earth that pulls all objects towards the

ground Free fall FALLING of an object without encountering any resistance from a height

towards the earth with an acceleration due to gravity Forces in equilibrium An object is said to be in a state of equilibrium when forces act upon an

object and it remains stationary or moves at a constant velocity Resultant force SINGLE FORCE which combines two or more forces which act on an object Work Work is done when a force causes an object to move in the direction of the

force. Energy CAPACITY of a system to do work Gravitational PE ENERGY STORED in the object because of its height above the earth

surface Elastic PE ENERGY STORED in the object as a result of stretching or compressing it Kinetic energy ENERGY possessed by a moving object Power RATE at which work is done or energy is changed and transferred Efficiency ABILITY of an electrical appliance to transform energy from one form to

another without producing useless energy or wastage Elasticity PROPERTY of an object that enables it to return to its original shape and

dimensions after an applied force is removed Spring constant FORCE needed to extend a spring per unit length Elastic limit MAXIMUM STRETCHING FORCE which can be applied to an elastic material

before it ceases to be elastic

Principle

Definition

Hooke’s Law Hooke’s law states that the force,F, applied to a spring is directly proportional to the spring’s extension or compression,x, provided the elastic

limit is not exceeded. Principle of conservation of

energy Principle of conservation of energy states that total energy in an isolated

system is neither increased nor decreased by any transformation. Energy

cannot be created nor destroyed, but it can be transformed from one kind to

another, and the total amount stays the same. Principle of conservation of

momentum The principle of conservation of momentum states that, in any collision or

interaction between two or more objects in an isolated system, the total

momentum of the system will remain constant; that is, the total initial momentum will equal the total final momentum.

Newton’s first law of motion Newton’s first law of motion states that a body will either remain at rest or

continue with constant velocity unless it is acted on by an external unbalanced force.

Newton’s second law of motion Newton’s second law of motion states that the acceleration a body experiences is directly proportional to the net force acting on it, and

inversely proportional to its mass.

F =ma

Newton’s third law of motion Newton’s third law of motion states that to every action there is an equal but

opposite reaction

Chapter 3: Forces and Pressures

Definition

Pressure FORCE acting normally on a unit surface area Gas pressure FORCE per unit area exerted by the gas particles as they collide with the

walls of their container (due to the rate of change of momentum) Buoyant force NET FORCE acting upwards due to the difference between the forces

acting on the upper surface and the lower surface

Principle

Definition

Law of Flotation Law of floatation states that the weight of an object floating on the

surface of a liquid is equal to the weight of water displaced by the object.

(weight of object = weight of water displaced) Pascal’s Principle Pascal’s principle states that a pressure applied to a confined fluid is

transmitted uniformly in all directions throughout the fluid. Archimedes’ principle Archimedes’ principle states that the buoyant force on a body immersed in a

fluid is equal to the weight of the fluid displaced by that object

(buoyant force = weight of water displaced) Bernoulli’s principle Bernoulli’s principle states that the pressure of a moving fluid decreases as

the speed of the fluid increases, and the converse is also true.

Chapter 4: Heat

Definition

Temperature DEGREE of hotness of an object Thermometric property PHYSICAL PROPERTY of a substance which is sensitive to and varies

linearly with the temperature change Thermal equilibrium A STATE when heat transfer between the two objects are equal and the

net rate of heat transfer between the two objects are zero Heat capacity HEAT ENERGY required to raise its temperature by 1°C or 1 K Specific heat capacity HEAT ENERGY required to produce 1°C or 1 K rise in temperature in a mass

of 1 kg. Latent heat HEAT ABSORBED OR RELEASED when a substance changes its state

without a change in temperature is called the latent heat of the substance Specific latent heat of fusion HEAT ENERGY required to change 1 kg of a substance from solid state to

liquid state, without a change in temperature Specific latent heat of

vapourisation HEAT ENERGY required to change 1 kg of a substance from liquid state to

gaseous state, without a change in temperature

Principle

Definition

Boyle’s Law Boyle’s Law states that the pressure of a fixed mass of gas is inversely

proportional to its volume provided the temperature of the gas is kept constant

(PV = k) Pressure Law The pressure law states that the pressure of a fixed mass of gas is directly

proportional to its absolute temperature (in Kelvin), provided the volume of

the gas is kept constant

(P/T = k) Charles’ Law Charles’ law states that the volume of a fixed mass of gas is directly

proportional to its absolute temperature (in Kelvin), provided the pressure of the gas is kept constant

(V/T = k)

Chapter 5: Light

Definition

Refraction PHENOMENON where the direction of light is changed when it crosses the

boundary between two materials of different optical densities as a result of a change in the velocity of light.

Apparent depth, d DISTANCE of the image from the surface of water

(or the boundary between the two mediums involved) Real depth, D DISTANCE of the object from the surface of the water

(or the boundary between the two mediums involved) Total internal reflection TOTAL REFLECTION of a beam of light at the boundary of two mediums,

when the angle of incidence in the optically denser medium exceeds a

specific critical angle Critical angle GREATEST ANGLE OF INCIDENCE in the optically denser medium for

which the angle of refraction, r = 90° Power of lens MEASURE OF ITS ABILITY to converge or diverge an incident beam of

light

Principle

Definition

Laws of Reflection the angle of incidence, i, is equal to the angle of reflection, r (i = r) the incident ray, normal and reflected ray will all lie in the same plane

Law of Refraction The incident ray and the refracted ray are on the opposite sides of the normal at the point of incidence, all three lie in the same plane

Obey Snell’s law

Snell’s Law The value of sin i is a constant. sin r

IMAGE CHARACTERISTICS

Definition

Virtual an image which cannot be projected (focused) onto a screen Real an image which can be projected (focused) onto a screen Laterally inverted an image which left and right are interchanged Upright an image which in vertical position Diminished image formed is smaller than the object Magnified image formed is larger than the object