(a) Telemeter and Multimeter:
Telemeter is used to convey the physical statistics to a distance, while a multimeter is a complex device, having a potentiometer and ammeter.
(b) Perimeter and Altimeter
Perimeter is a conceptual term, while the altimeter is a device, for measuring the altitudes.
(c) Periscope and Microscope
In microscope, the channel of light waves is straigt, while in a periscope, it is bended by the use of a mirror o a prism.
(d) Nucleon and Photon
Nucleon is a sub-nuclear particle, while a photon is n energy packet.
(e) Cusec and Comet
Cusec is a measure of flow, while comet is an object.