A device to measure atmospheric pressure.
A series of sharp spectral lines in the hydrogen spectrum. Named after J.J. Balmer.
A unit of pressure nearly identical to the atmosphere unit. One bar = 750.062 torr = 0.9869 atm = 100,000 Pa.
Is a derived SI unity of radioactivity. 1 Bq one atom per second will decay. Named after Antoine Henri Becquerel.
A radioactive process in which a neutron changes into a proton and emits an electron and an anti-neutrino.
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.