Topic
Measurements
4 questions tagged Measurements — spanning every one of the seven Ws.
what
What is atomic mass?
Atomic mass is the average mass of an element’s atoms, taking isotopes into account. It is usually shown in atomic mass units on the periodic table.
ChemistryMeasurements
what
What is a mole in chemistry?
A mole is a counting unit used in chemistry, equal to about 6.022 × 10^23 particles. It lets chemists connect tiny atoms to measurable amounts of पदार्थ.
ChemistryMeasurements
how
How do astronomers measure the distance to a star?
For nearby stars, they use parallax — the tiny shift in a star’s position as Earth orbits the Sun. The closer the star, the larger the shift.
SpaceMeasurements
how
How do scientists tell how fast a galaxy is moving away from us?
They measure the redshift of its spectral lines. A larger redshift means the galaxy is receding faster on average.
SpaceMeasurements