What type of celestial body, left over from the formation of our own solar system, is a rock-like object smaller than a planet?
Hundreds of thousands of asteroids are located in the "asteroid belt," a region of space between Mars and Jupiter. The largest asteroids are almost 600 miles in diameter.
Which 20th-century German-born physicist is considered the father of modern physics, thanks to his development of the general theory of relativity?
Although he won the 1921 Nobel Prize in Physics for his work pertaining to the photoelectric effect (which helped lead to quantum theory), he is best known for his mass-energy equivalence formula E=mc2, which helped lead to the development of nuclear fission.
What landmark historical event occurred on July 20, 1969?
On this day, the first humans set foot on the moon.
Three Americans were on this mission aboard Apollo 11: Neil Armstrong, Buzz Aldrin, and Michael Collins. Armstrong became the first man to walk on the moon, and made the iconic statement, "one small step for [a] man, one giant leap for mankind."
Sound is measured in ___.
- 10 dB: silence
- 60 dB: conversation
- 85 dB: hearing damage possible
- 120 dB: rock concert (front row)
- 140 dB: hearing damage will occur without protection
- 165 dB: jet takeoff
What is the difference between an atom, an element, and a molecule?
Atoms are tiny units of matter made of neutrons, protons, and electrons
- An element is a pure chemical substance consisting of a single type of atom (e.g. hydrogen, carbon, neon.) The 118 elements currently known are summarized in the Periodic Table
- A molecule is a group of two or more atoms held together by chemical bonds
Which 20th- and 21st-century English physicist wrote the famous science nonfiction book A Brief History of Time in 1988?
He is renowned for his work on general relativity, black holes, and quantum mechanics, and is currently the Director of Research at the Centre for Theoretical Cosmology at the University of Cambridge. Hawking suffered from ALS, a neurological disease that paralyzed him. Hawking passed away in March 2018.
This branch of physics deals with sound and waves.
One practical application of acoustics deals with the design of buildings, such as concert halls and recording studios. Recording rooms are designed to absorb sound, typically using a foam or cloth material. Concert halls, on the other hand, are designed to reflect and scatter sound.
What celestial body releases gas or dust and is made of ice and other materials left over from the Big Bang?
Comets can be seen from Earth, leaving a visible trail of gas and dust. This spectacle is commonly referred to as a meteor shower. It is believed that some of the organic compounds that make up our water and made early life possible traveled to Earth by comet.
Why does dry ice produce a smoky substance?
The smoke is the gaseous form of carbon dioxide.
The substance that we colloquially refer to as "dry ice" is actually the frozen form of carbon dioxide, and is about -100º F. When introduced to our surroundings, the carbon dioxide begins to melt. However, since it can only reach its liquid form in high-pressure environments, it changes directly from solid to gas.
Which 19th- and 20th-century Polish physicist was the first woman to win a Nobel Prize?
She is best known for her research on radioactivity and the techniques of isolating radioactive isotopes.
What was the first satellite launched by humans on October 4, 1957?
The satellite was launched by Russia and traveled for 92 days in space before burning up in the atmosphere upon its return. Sputnik has historical significance, as it led to the Space Race between the United States and Russia in a time where tensions were already high as a result of the Cold War.
___ energy is the energy of an object in motion; ___ energy is the stored energy of an object based on its current state or position.
For example, a skiier has lots of potential energy at the top of a slope. However, when he begins to ski down the mountain, that energy becomes kinetic due to his motion.
What is pH a measure of?
pH is a measure of how acidic or basic a substance is, ranging from 0 (most acidic) to 14 (most basic).
- Orange juice is acidic and has a pH level of 4
- Water is neutral and has a pH level of 7
- Bleach is basic and has a pH level of 13
Which American inventor of the 19th and 20th centuries patented more than a thousand devices and aided in the development and design of numerous others, such as the incandescent lightbulb?
Other devices that Edison worked on or was influential in the development of include the phonograph, the motion picture camera, and power stations and generators.
What event, believed to have occurred 13.8 billion years ago, may mark the inception of our universe?
The Big Bang
The universe started in a small, dense, and hot state, then began expanding and cooling. Evidence for the Big Bang is found in the form of Cosmic Microwave Background radiation.
Which American physicist of the 20th century is known as the "father of the atomic bomb?"
John Robert Oppenheimer
He played a major role in the Manhattan Project, which developed the first nuclear weapons.
How do 3D glasses work?
3D glasses take advantage of humans' naturally existing binocular vision.
Traditional 3D glasses have one red and one blue lens. The movie actually projects two images, one red and one blue, resulting in the red image going to one eye (red lens) and the blue image going to the other eye (blue lens). This gives the illusion of 3D.
In electricity, what is the difference between AC and DC?
AC, or alternating current, means that electricity flows in both directions. This is the type of current that runs through our homes. DC, or direct current, means that electricity only flows in one direction. This is the type of current that is produced by a battery.
Real world example: When you plug your cell phone in to charge at your house, the power cord transforms the alternating current running through your home to direct current that will charge your device.
Which 17th- and 18th-century English scientist played an enormous role in developing the modern understanding of subjects including calculus, light, motion, and gravity?
He is considered one of the greatest scientists in human history.
Why does metal spark in a microwave?
Metal reflects the radiation rather than absorbing it.
Microwaves heat food using electromagnetic radiation, which freely passes through container materials such as glass and plastic. However, this radiation is not absorbed and does not pass through metal. Instead, it reflects, which can lead to damage to the microwave, electrical sparks, or fire.
How does a battery work?
Batteries use a chemical reaction to produce energy.
A discharging battery has a positive end (cathode) and a negative end (anode). When the battery is connected to an appliance (load), a chemical reaction occurs within the battery and an electrical charge is produced. A battery eventually stops working when the chemical reaction can no longer continue.
Which 19th- and 20th-century Scottish-American inventor is credited with the invention of the telephone?
Alexander Graham Bell
He devoted much of his research and career to elocution, hearing, speech, and the education of the deaf. He also helped found the National Geographic Society.
Why do boats and other large objects stay afloat in bodies of water?
These objects remain above water because they are less dense than the water they displace.
In chemistry, what is the difference between an element and a compound?
- An element is made up of only one type of atom (e.g. oxygen).
- A compound is made up of more than one type of atom (e.g. H2O: two hydrogen atoms and one oxygen atom form water).
Which wealthy Swedish scientist and arms manufacturer of the 19th century invented dynamite?
After his death, his fortune was used to establish the Nobel Prizes, awards for cultural and scientific achievement. Famous Nobel Prize winners include Albert Einstein, Marie Curie, and Martin Luther King, Jr.
In chemistry, what is the difference between ionic and covalent bonds?
- A covalent bond forms between a non-metal and another non-metal.
Ionic bonds result when atoms have an electrostatic attraction. An ionic bond forms between a non-metal and a metal.
Which 19th-century English scientist is most famous for establishing the notion of the electromagnetic field in physics?
He is credited with discovering diamagnetism (which creates a magnetic field), electromagnetic induction, and the laws of electrolysis.
How is laser light different from other types of light?
Lasers are brighter and more concentrated than regular light.
Lasers are produced by exciting electrons and directing them to project at the same time and direction, producing single-wavelength light. Low-power lasers are used in laser pointers and CD players. High-power lasers are used in nuclear fusion, to cut hard materials, and in certain surgical applications.
Which 20th-century American scientist and author gained widespread popularity for his 1980 television series Cosmos: A Personal Voyage, and its accompanying book by the same name?
Sagan was a celebrated astronomy researcher who studied the surface temperatures of Venus and the possibility of extraterrestrial life.
What is Newton's First Law of Motion?
An object at rest stays at rest and an object in motion stays in motion, unless an outside force acts on it.
Example: A ball rolling on the ground would continue to roll without stopping if it did not experience friction from the ground and the air.