Grade 10 IEB Science Essentials

Flashcards to help Grade 10 Science students learn Essentials of physics and chemistry.

Pulse

A single disturbance in a medium.

Transverse Pulse

A pulse in which the particles of the medium move at right angles to the direction of motion of the pulse.

Interference

The overlapping of two pulses when they coincide, meeting at the same point at the same time.

Superposition

The algebraic sum of the amplitudes of two pulses that occupy the same space at the same time.

Constructive Interference

The phenomenon where the crest of one pulse overlaps with the crest of another to produce a pulse of increased amplitude.

Destructive Interference

The phenomenon where the crest of one pulse overlaps with the trough of another, resulting in a pulse of reduced amplitude.

Rest Position

The position from which all particles start from and return to after a pulse or wave has passed.

Amplitude

The maximum displacement of particles from the rest position.

Pulse Length

The distance between the start and end of a pulse.

Transverse Wave

A wave in which the particles of the medium vibrate at right angles to the direction of motion of the wave.

Wavelength (λ)

The distance between two consecutive points in phase on a wave.

Crest

The highest point (peak) on a wave.

Trough

The lowest point on a wave.

Points in Phase

Two points separated by a whole number multiple of completed wavelengths, following the exact same path with identical motion.

Points Totally Out of Phase

Two points following exactly the opposite path.

Points Partially Out of Phase

Points not separated by a whole number multiple of completed wavelengths, following different paths.

Wave Speed

The distance traveled by a point on a wave per unit time.

Frequency (f)

The number of waves per second, measured in Hertz (Hz).

Period (T)

The time taken for one complete wave, measured in seconds (s).

Longitudinal Wave

A wave in which the particles of the medium vibrate parallel to the direction of motion of the wave.

Compression

A region of high pressure in a longitudinal wave.

Rarefaction

A region of low pressure in a longitudinal wave.

Echo

Waves are reflected by large hard flat surfaces; the reflection of the sound wave.

Ultrasound

Sound waves of a higher frequency than we can hear (20 kHz to 100 kHz).

Photons

Electromagnetic radiation transfers energy to other matter in packets.

Photon

A quantum of EM radiation (which carries a set amount of energy)

Magnetic field

Region in space where another magnet or ferromagnetic material will experience a non-contact force

Non-contact force

A force exerted on an object without touching the object.

Magnet

An object with a pair of opposite poles, called north and south.

Ferromagnetic Materials

Materials which are strongly attracted by magnets and are easily magnetised. Common materials include iron, cobalt, nickel and their alloys.

Geographical north pole

Point in the northern hemisphere where the rotation axis of the earth meets the surface.

Magnetic north pole

The point where the magnetic field lines of the earth enters the earth and the direction in which a compass needle points.

Angle of declination

The angle between the true North Pole and the magnetic North Pole

Magnetic field

Area in which a magnetic material experiences a magnetic force.

Electric field

Area in which an electric charge experiences an electric force.

Gravitational field

Area in which a mass experiences a gravitational force.

Electrostatics

All materials contain positive charges (protons) and negative charges (electrons).

Quantisation of charge

The charge on a single electron is − 1,6 × 10−19 C.

Principle of conservation of charge

The net charge of an isolated system remains constant during any physical process.

Electricity

The process of giving energy to a charge and then using that energy to do work.

Resistance

Opposition to the flow of electric current.

Ohm's Law

The current in a conductor is directly proportional to the potential difference across it provided its temperature remains constant.

Potential difference

The energy transferred per unit electric charge that flows through it.

Emf

The voltage measured across the terminals of a battery when no current is flowing through the battery (the switch is open).

Potential difference (pd)

The voltage measured across the terminals of a battery when current is flowing through the battery.

Scalar

A physical quantity with magnitude only.

Vector

A physical quantity with both magnitude and direction.

Net or Resultant Vector

The single vector that has the same effect as two or more vectors together.

Position (x)

The place where an object is relative to a specific reference point. Position is a vector. Unit is meter(m).

Reference Point

A point from which the position of the object is measured (zero point).

One Dimensional Motion

Motion that occurs either vertically or horizontally along a straight line.

Distance

The total path length travelled.

Displacement

Difference in position in space, measured from start to final position.

Speed (v)

Rate of change of distance with time. Scalar, unit is m.s⁻¹.

Velocity (v ⃗)

Rate of change of position. Vector, unit is m.s⁻¹.

Acceleration ( a )

Rate of change of velocity. Vector, unit is m.s⁻².

Deceleration

Non-scientific term that means an object is slowing down. In science we rather refer to acceleration → direction and context describe whether it is speeding up or slowing down.

Ticker Timers

A device which produces a series of dots on a tape which can be analyzed to determine the displacement between two points and the time taken between the two points.

Position (x)

The place where an object is relative to a specific reference point.

Distance (D)

Length of path taken by a moving object.

Displacement (∆x)

Change in position with respect to a start point.

Speed (v)

Rate of change of distance.

Energy

The ability to do work, measured in joules (J).

Gravitational Potential Energy (EP)

The energy an object possesses due to its position in the gravitational field relative to a reference point.

Kinetic Energy (EK)

The energy an object possesses as a result of its motion

Mechanical Energy (EM)

The sum of gravitational potential and kinetic energy at a point.

Law of conservation of energy

The total energy of an isolated system remains constant.

Principle of conservation of mechanical energy

The total mechanical energy in an isolated system remains constant.

Mixture

Consists of different particles, not chemically joined.

Compound

Consists of two or more elements chemically bonded

Element

Consists of only one type of atom.

Insulator

A material that prevents the flow of charge.

Electrical Conductor

A material that allows the flow of charge.

Semi-Conductor

A substance that can conduct electricity under certain conditions.

States of matter

One-dimensional solids, liquids and gases

Atoms combine in very specific ratios to form certain compounds

These ratios remain fixed for that compound and given by the formula.

Ions

Simple ions are single atoms which carry a charge. They are also called monatomic ions

Law of conservation of matter

This law means that matter cannot be created or destroyed, merely transferred from one substance to another

Kinetic Theory of Matter

All matter has mass and takes up space.

Changing of States

Heating and cooling curves for substance with one state

Brownian Motion

The random movement of microscopic particles suspended in a gas or liquid..

Models of the Atom

Democritus proposed that if you kept cutting a substance in half repeatedly, you would eventually end up with an “uncuttable” particle called atoms.

Models of the Atom

That all elements are made up of small, indestructible, s o l i d s p h e r e s called atoms.

Models of the Atom

That Thomson used cathode ray to show that there are small negative parti- cles inside atoms called electrons.

Models of the Atom

Rutherford conducted with alpha particles shows that i.The positive charge is not evenly distributed as suggested by Thomson but is in the centre of the

Models of the Atom

That electrons travel around the nucleus in circular, definite paths called orbits

Models of the Atom

That the regions inside an atom where electrons are likely to be found are called orbitals.

What is an atom

Identified by the contents of the nucleus with the notation AEZ.

What is the atomic arrangement

Arrangement of energy levels inside the atom.

Ionisation Energy

Energy needed per mole to remove an electron from an atom in the gaseous phase.

Period Trends

Electronegativity is from 0,7 (Cs) to 4,0 (F). Tendency of an atom in a molecule to attract bonding electrons.

Chemical bonds

Are INTRAMOLECULAR BONDS which occur between atoms within molecules to a full electron shell.

Covalent bond

Sharing of at least one pair of electrons by two non-metal atoms to form a molecule.

Ionic bond

Involves a complete transfer of electron(s) with metal(s) to form ions.

Metallic Bonding

Occurs between a metal and a metal atom due to a strong but flexible bond between the positive metal kernels and as sea of delocalized electrons.

Physical change

Usually easy to reverse with small energy changes involved. No new substances formed. The particles stay the same, but their arrangement changes.

Chemical change

Usually hard to reverse, forming a new substances with large energy changes involved.The mass is conserved, but the atoms have been rearranged.

Law of conservation

Law in a chemical reaction, the sum of the mass of the reactants equals the sum of the mass of the products.

Aqueous solutions hydration of ions

The ions of the solute become totally surrounded by water molecules form what process

Aqueous Solutions reactions

Is a reaction where reaction takes place between acids and bases