Key Discoveries in Physics and Medicine

Study Notes

Wilhelm Conrad Röntgen

German physicist who discovered X-rays in 1895
X-rays are electromagnetic rays that can pass through human skin but are blocked by denser materials like bone and metal
His discovery revolutionized medical imaging and earned him the first Nobel Prize in Physics in 1901

Ivan Pavlov

Russian physiologist known for research on digestive secretions in dogs
Discovered classical conditioning: a dog can learn to associate the sound of a bell with the arrival of food, eventually salivating at the sound of the bell alone
Won the Nobel Prize in Physiology or Medicine in 1904 for his work on digestion

Kitasato Shibasaburo

Japanese bacteriologist who studied in Tokyo and Berlin
Developed serum therapy to protect against tetanus and diphtheria
Discovered a tetanus serum containing antitoxin that could be injected into animals exposed to tetanus bacteria to create immunity

### J.J. Thomson

English physicist who described the structure of atoms using a cathode ray tube
Identified “corpuscles” (electrons) as negatively charged particles about 2,000 times lighter than hydrogen atoms
Proposed the plum pudding model: atoms consist of electrons embedded in a sphere of positive charge

### Jules Henri Poincaré

French mathematical physicist known for his work on stability of the solar system
Noticed that even small changes in initial conditions can lead to large, unpredictable outcomes in complex systems, contributing to chaos theory

### Svante Arrhenius

Swedish physicist who theorized that past ice ages might have been caused by fewer volcanic eruptions
Proposed that volcanic gases like carbon dioxide trap heat in the atmosphere, so fewer eruptions would cool the Earth
Linked human activities like burning fossil fuels to rising global temperatures, laying the groundwork for modern climate change concerns

### Annie Jump Cannon

American astronomer who classified over 350,000 stars
Developed the Harvard Spectral Classification System, a standard method for categorizing stars based on their spectra
Dedicated over 44 years to stellar classification, becoming a leading authority on stellar spectra in the 20th century

### Henrietta Swan Leavitt

American astronomer who discovered a relationship between the brightness and period of Cepheid variable stars
Her work became essential for determining distances to other galaxies by measuring the brightness of Cepheid variable stars
Discovered over 2,400 variable stars and four novae

### Harriet Brooks

Canadian physicist who studied under J.J. Thomson and Marie Curie
Became Canada's first female nuclear physicist
Made discoveries about nuclear decay and worked on groundbreaking research in radioactivity

### Srinivasa Ramanujan

Indian mathematician who made significant contributions to number theory despite limited formal training
Invited to Cambridge in 1913 and received a Bachelor of Science degree in 1916
Became the second Indian to be elected a Fellow of the Royal Society

### Ronald Fisher

British statistician and geneticist who pioneered the application of statistics to scientific experiments
Published a paper in 1918 illustrating how to use statistical tools to reconcile Darwin’s theory of natural selection with Mendel’s experiments on heredity

### Erwin Schrödinger

Austrian physicist recognized for his work in quantum physics
Developed the Schrödinger wave equation which provided a new understanding of how particles behave, shifting from orbiting electrons to “clouds” of probability for electron position

### Harold Urey and Stanley Miller

American chemists who recreated early Earth conditions in a lab in 1953
Used a series of connected glass flasks containing water and gases such as ammonia and methane, simulating early Earth’s atmosphere.
Mimicked early Earth’s conditions with electrical sparks to create simple carbon-based compounds, demonstrating the possibility of life formation in early Earth.

Description

Explore the groundbreaking contributions of notable scientists such as Wilhelm Conrad Röntgen, Ivan Pavlov, Kitasato Shibasaburo, and J.J. Thomson. This quiz highlights their discoveries and the impact these had on physics and medicine, including concepts like X-rays and classical conditioning. Test your knowledge on these pivotal advancements in science and their pioneers.