HardJava
Java Quiz: advanced memory, threads and modern API
Test your advanced Java knowledge: heap and stack, garbage collector, immutable String, threads, synchronized, volatile, ExecutorService, Optional and records.
Science quizzes
Physics, chemistry, biology, astronomy
The Science theme brings together the main disciplines that explain the world: physics, chemistry, biology and astronomy, along with geology and medicine. You will meet figures such as Galileo, Newton, Marie Curie, Pasteur and Einstein, discoveries like gravity, radioactivity, penicillin and the structure of DNA, and basic notions such as atoms, energy, cells and the solar system.
Science quizzes test both general scientific knowledge and reasoning, with questions on the experimental method, units of measurement and great inventions. You can play without paying: each quiz has five difficulty levels from very easy to expert, and a short comment explaining every answer.
Subthemes
Quizzes
MediumJava
Java Quiz: OOP, inheritance, interfaces and collections
Test your object-oriented programming knowledge in Java: inheritance, interfaces, encapsulation, static, exceptions, collections, generics and equals.
EasyJava
Java Quiz: language basics, types and syntax
Test your Java basics: its creator, the JVM, the JDK and the JRE, the boolean and char types, String, arrays, the main method and class names.
Frequently asked questions about Science
What is the speed of light in a vacuum?
Light travels in a vacuum at exactly 299,792,458 meters per second, or roughly 300,000 kilometers per second. This value, written c, is a fundamental constant of physics: according to Einstein's special relativity, no information can travel faster.
What is the scientific method?
It is an approach that starts with observing a phenomenon, forms a hypothesis, tests it with controlled experiments, analyzes the results and draws a conclusion. Results must be reproducible by other researchers and can be challenged by new evidence.
Who discovered penicillin and how?
Scottish bacteriologist Alexander Fleming discovered penicillin in 1928, when a Penicillium mold that had accidentally landed on a culture dish stopped bacteria growing around it. Howard Florey and Ernst Chain later turned it into a usable drug in the 1940s.