General Science Quiz: Chemistry, Biology & Physics

The Sun produces heat through nuclear fusion, not combustion. Combustion is a chemical reaction with oxygen, while the Sun's core fuses hydrogen into helium through nuclear processes at extremely high temperatures and pressures.

Energy from motion is kinetic energy, not potential energy. Potential energy depends on an object's position or state in a force field (like gravitational height), while kinetic energy depends on its velocity and mass.

The kinetic energy formula is KE = 1/2 mv², where m is mass and v is velocity. The square of velocity is crucial - doubling velocity quadruples kinetic energy, showing why speed matters more than mass in many collision scenarios.

Work and heat are both forms of energy transfer, measured in joules (SI unit). While they have the same unit, they represent different processes - work is organized energy transfer via force, while heat is disorganized transfer due to temperature differences.

Power is defined as the rate at which work is done or energy is transferred. The formula is Power = Work/Time, measured in watts (joules per second). A higher power device does the same work faster.

This statement is the Law of Conservation of Energy (First Law of Thermodynamics). It states that in an isolated system, total energy remains constant - energy can only change forms (like potential to kinetic), not appear or disappear.

Work against gravity is W = mgh = 90 kg × 9.8 m/s² × 10 m = 8820 J. This is the gravitational potential energy gained. When lifting against gravity, work equals force (weight) times vertical distance.

Work done against friction is W = F × d = 67 N × 8 m = 536 J. The applied force must at least equal friction to maintain motion. This work becomes thermal energy dissipated as heat.

Work is defined as force applied through a displacement (distance). The formula W = F × d requires both a force component in the direction of motion and some displacement. No movement means zero work, regardless of force applied.

Energy is defined as the capacity or ability to do work. This fundamental concept means any object or system possessing energy can potentially exert forces and cause displacement. Different energy forms (kinetic, potential, thermal) all share this capacity to perform work.

Batteries convert stored chemical energy into electrical energy through electrochemical reactions. When the battery discharges, chemical reactions release electrons that flow as current, converting potential chemical energy into usable electrical energy for external circuits.

Rafflesia arnoldii is the world's largest flower, found in rainforests of Southeast Asia (mainly Borneo and Sumatra). It can grow up to 1 meter in diameter and weighs up to 11 kilograms. Lotus and rose are much smaller.

The liver is the largest gland in the human body (weighing about 1.5 kg) and also the largest internal organ. It performs over 500 functions including detoxification, protein synthesis, and bile production. Pancreas is a gland but much smaller.

Dmitri Mendeleev published his periodic table in 1869, arranging elements by atomic weight and predicting properties of undiscovered elements. This was a breakthrough in organizing chemical knowledge.

Dmitri Mendeleev and Lothar Meyer independently developed periodic tables in 1869-1870, though Mendeleev's version was more comprehensive and made predictions about undiscovered elements.

Aurum is the Latin word for gold, which is why the chemical symbol for gold is Au. Many element symbols derive from their Latin names.

The rows of the periodic table are called periods. Each period represents a new principal energy level being filled with electrons as you move across the table.

The columns of the periodic table are called groups. Elements in the same group have similar chemical properties because they have the same number of valence electrons.