Studied by 0 people
What is a vector?
A physical quantity that has both magnitude and direction, e.g., velocity.
What is a scalar quantity?
A physical quantity that has magnitude only, e.g., temperature.
What is a resultant vector?
The single vector which has the same effect as the original vectors acting together.
Define distance.
The length of path travelled; it is a scalar quantity.
What is displacement?
The change in position; it is a vector quantity.
Define speed.
The rate of change of distance; it is a scalar quantity.
What is velocity?
The rate of change of position or displacement; it is a vector quantity.
Define acceleration.
The rate of change of velocity.
What is weight (Fg)?
The gravitational force the Earth exerts on any object on or near its surface.
Define normal force (FN).
The perpendicular force exerted by a surface on an object in contact with it.
What is frictional force (Ff)?
The force that opposes the motion of an object, acting parallel to the surface.
State Newton's first law.
An object continues in a state of rest or uniform velocity unless acted upon by a net force.
What is inertia?
The property of an object that causes it to resist a change in its state.
State Newton's second law.
When a net force is applied to an object, it accelerates in the direction of the net force.
What does Newton's second law state regarding acceleration?
The acceleration is directly proportional to the net force and inversely proportional to mass.
State Newton's third law.
When object A exerts a force on object B, B exerts an equal and opposite force on A.
Define linear momentum.
The product of the mass and velocity of the object.
How is Newton's second law expressed in terms of momentum?
The net force acting on an object is equal to the rate of change of momentum.
What is the law of conservation of linear momentum?
The total linear momentum of an isolated system remains constant.
Define an elastic collision.
A collision in which both momentum and kinetic energy are conserved.
What is an inelastic collision?
A collision in which only momentum is conserved.
Define impulse (J).
The product of the net force and the contact time.
Define work done on an object by a force.
The product of the displacement and the component of the force parallel to the displacement.
What is gravitational potential energy?
The energy an object possesses due to its position relative to a reference point.
Define kinetic energy.
The energy an object has as a result of its motion.
What is mechanical energy?
The sum of gravitational potential and kinetic energy at a point.
State the law of conservation of energy.
The total energy in a system cannot be created nor destroyed; only transformed.
What is the principle of conservation of mechanical energy?
In the absence of external forces, mechanical energy of an object is constant.
State the work-energy theorem.
The work done by a net force is equal to the change in kinetic energy of the object.
Define power.
The rate at which work is done or the rate at which energy is transferred.
What is the unit of power?
The watt (W); one watt is the power when one joule of work is done in one second.
Define efficiency.
The ratio of output power to input power.
State Newton's law of universal gravitation.
Every particle with mass attracts every other particle with a force proportional to their masses and inversely proportional to the square of the distance.
What is the gravitational field?
The force acting per unit mass.
State Coulomb's law in words.
Two charges exert forces on each other proportional to the product of the charges and inversely to the square of the distance between them.
Define the magnitude of the electric field.
The force per unit positive charge.
What is potential difference?
The work done per unit positive charge.
Define current.
The rate of flow of charge.
State Ohm's law.
Current through a conductor is directly proportional to the potential difference at constant temperature.
What is resistance?
A material's opposition to the flow of electric current.
Define emf.
The total energy supplied per coulomb of charge by a cell.
What is magnetic flux linkage?
The product of the number of turns on the coil and the magnetic flux through the coil.
State Faraday's law of electromagnetic induction.
The emf induced is directly proportional to the rate of change of magnetic flux.
State Lenz's law.
The induced current flows in a direction to oppose the change in magnetic flux.
Define a diode.
A component that allows current to flow in one direction only.
What is the threshold frequency (fo)?
The minimum frequency of incident radiation for electron emission from a metal.
Define work function (Wo).
The minimum energy needed to emit an electron from a metal surface.
What is molar mass?
The mass in grams of one mole of a substance.
Define solution.
A homogenous mixture of solute and solvent.
What is a solute?
The substance that is dissolved in a solution.
Define solvent.
The substance in which another substance is dissolved.
What is concentration?
The amount of solute per unit volume of solution.
Define yield in chemistry.
A measure of the extent of a reaction compared to the maximum possible amount of product.
What is an intramolecular bond?
A bond which occurs between atoms within molecules.
Define a covalent bond.
A sharing of at least one pair of electrons by two non-metal atoms.
What is a non-polar covalent bond?
An equal sharing of electrons.
Define a polar covalent bond.
Unequal sharing of electrons, resulting in a dipole.
What is electronegativity?
A measure of an atom's tendency to attract a bonding pair of electrons.
Define an ionic bond.
A transfer of electrons and the electrostatic attraction between ions.
What is metallic bonding?
Bonding between a positive kernel and a sea of delocalised electrons.
Define intermolecular force.
A weak force of attraction between molecules, ions, or noble gas atoms.
What is heat of reaction (∆H)?
The net change of chemical potential energy of the system.
Define exothermic reaction.
Reactions that transform chemical potential energy into thermal energy.
Define endothermic reaction.
Reactions that transform thermal energy into chemical potential energy.
What is activation energy?
The minimum energy required to start a chemical reaction.
Define the activated complex.
A temporary transition state between reactants and products.
What is reaction rate?
The change in concentration per unit time of a reactant or product.
Define a catalyst.
A substance that increases the rate of reaction but remains unchanged.
What is a closed system in chemistry?
A system where mass is conserved but energy can enter or leave.
Define an open system in chemistry.
A system where both energy and matter can be exchanged with surroundings.
State Le Châtelier's principle.
When an external stress is applied, the system will adjust to counteract the stress.
Define acid and base according to the Lowry-Brønsted model.
Acid: proton donor; Base: proton acceptor.
What is ionisation?
The reaction of a molecular substance with water to produce ions.
Define a strong acid.
An acid that ionises completely in an aqueous solution.
What is a weak acid?
An acid that only ionises partially in an aqueous solution.
Define dissociation.
The splitting of an ionic compound into its ions.
What is a strong base?
A base that completely dissociates in an aqueous solution.
Define a weak base.
A base that only partially dissociates or ionises in an aqueous solution.
What is an amphoteric substance?
A substance that can act as either an acid or a base.
Define Kw for water at 25 °C.
Kw = [H3O+][OH-].
What is a salt?
A substance where the hydrogen of an acid has been replaced by a cation.
Define hydrolysis of a salt.
A reaction of an ion from a salt with water.
What is neutralisation?
The point where an acid and base have reacted so neither is in excess.
Define a standard solution.
A solution of known concentration.
What is a redox reaction?
A reaction involving the transfer of electrons.
Define oxidation.
The loss of electrons.
What is reduction?
The gain of electrons.
Define an oxidising agent.
A substance that accepts electrons.
What is a reducing agent?
A substance that donates electrons.
Define anode.
The electrode where oxidation takes place.
What is a cathode?
The electrode where reduction takes place.
Define an electrolyte.
A substance that can conduct electricity by forming free ions.
What is a hydrocarbon?
A compound containing only carbon and hydrogen atoms.
Define a saturated compound.
A compound where all bonds between carbon atoms are single bonds.
What is an unsaturated compound?
A compound with at least one double and/or triple bond between carbon atoms.
Define a functional group.
An atom or group of atoms that form the center of chemical activity in a molecule.
What is an homologous series?
A series of similar compounds with the same functional group, differing by a single CH2 unit.
Define structural isomers.
Compounds with the same molecular formula but different structural formulae.
Note 
Flashcard (119)