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Glossary B

Barometer
A device to measure atmospheric pressure.
Balmer series
A series of sharp spectral lines in the hydrogen spectrum. Named after J.J. Balmer.
Bar
A unit of pressure nearly identical to the atmosphere unit.
One bar = 750.062 torr = 0.9869 atm = 100,000 Pa.
Becquerel (Bq)
Is a derived SI unity of radioactivity. 1 Bq one atom per second
will decay. Named after Antoine Henri Becquerel.
Beta decay
A radioactive process in which a neutron changes into a proton
and emits an electron and an anti-neutrino.
Bimetallic strip
A strip of two metals joined together and as different metals
will expand and contract at different rates, the strip will buckle
with a change in temperature. Used in thermostats. [More]
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