sec 1 g3 Density, Speed, Energy, Force, Mixtures, and Cells end of year revision

study for your end of year exams!

What is density

Density is the amount of mass in a given volume of a substance

What is the formula for density

Density = Mass ÷ Volume

What is the unit for density

The unit for density is kilograms per cubic metre (kg/m³) or grams per cubic centimetre (g/cm³)

What happens to an object’s density when its volume increases but mass stays the same

The density decreases

What happens when an object has a higher density than the liquid it is in

It sinks

What is speed

Speed is the distance travelled per unit time

What is the formula for speed

Speed = Distance ÷ Time

What are the common units for speed

The common units are metres per second (m/s) or kilometres per hour (km/h)

What happens to speed when distance increases but time stays the same

The speed increases

What does a distance time graph show?

A distance-time graph shows how far an object travels over a given period

What is energy

Energy is the ability to do work or cause change

What are the main types of energy

The main types are kinetic, potential, heat, light, sound, and electrical energy

What is kinetic energy

Kinetic energy is the energy of a moving object

What is potential energy

Potential energy is stored energy due to an object’s position or state

What is the law of conservation of energy

Energy cannot be created or destroyed, only converted from one form to another

What is force

A force is a push or pull that can change the motion or shape of an object

What is the formula for force

Force = Mass × Acceleration

What is the SI unit of force

The SI unit of force is the newton (N)

What is weight

Weight is the force of gravity acting on an object’s mass

What is the difference between balanced and unbalanced forces

Balanced forces cause no change in motion, while unbalanced forces cause acceleration

What is a mixture

A mixture is made up of two or more substances that are not chemically combined

What are the two types of mixtures

Homogeneous mixtures have uniform composition, while heterogeneous mixtures do not

What are common methods to separate mixtures

Filtration, evaporation, distillation, and chromatography

What is the difference between a compound and a mixture

A compound has chemically bonded elements, while a mixture does not

Give an example of a mixture

Air is a mixture of gases such as nitrogen and oxygen

What is a cell

A cell is the basic unit of life that carries out life processes

What are the main parts of a plant cell

Cell wall, cell membrane, cytoplasm, nucleus, chloroplast, and vacuole

What are the main parts of an animal cell

Cell membrane, cytoplasm, and nucleus

What is the function of the cell membrane

It controls the movement of substances in and out of the cell

What is the function of the nucleus

It controls cell activities and contains genetic material

What is the function of the cytoplasm

It is a jelly-like consistency

What is the difference between plant and animal cells

Plant cells have a cell wall and chloroplasts, while animal cells do not