- particle leakage
- particle separation
- particle trajectory
- particlescattering
- partition
- partition function
- pasteur pipette
- path difference
- pauli principle
- peak torque
- peak
- pebble bed
- pedestal
- pedometer
- peen
- pellet stack
- pendular
- pendulum bearing
- pendulum deflection
- pendulum error
- pendulum length
- pendulum mill
- pendulum orbit
- pendulum sphere
- pendulum swing
- penetrating power
- penetration potential
- penstock
- pentatonic scale
- penumbral
- perfect gas
- pencil
- pendulum mass
- pendulum test
- penetration factor
- penetration method
- pentode
- penumbrous
- percussion mortar
- perfect fifth
- period
- period range
- periodic flowing
- periodic group
- periodic motion
- periodic oscillation
- periodic shutdown
- periodic tone
- periodical vibration
- peripheral nucleon
- periscopic
- peristaltic pump
- perturbed frequency
- petrophysics
- pfund series
- periodogram
- peripheral gas
- periscopic lens
- personal dosimetry
- phase
- phase demodulation
- phenolic lining
- phial
- phonetic power
- phonon
- photo-pion
- photocathode
- photoconducing drum
- photoconducing layer
- photodetachment
- photodeuteron
- photodiode
- photodisintegration
- photodynamic
- photoelectric threshold
- photoelectron spectroscopy
- photoemissive
- photoemissive layer
- photoetching process
- photoflood bulb
- photographic method
- photohalide
- photometer
- photometric Intensity
- photometric paradox
- photon
- photoneutron
- photonics
- photoproton
- photoreproduction methods
- photoresist layer
- photoresistor
- physical balance
- physiological noise
- pile
- pipette
- phon
- phonation
- phonometer
- phosphor