1. Pressure: Barometer
2. Voltage: Voltmeter
3. Purity of Milk: Lactometer
4. Temperature: Thermometer
5. Velocity of Wind: Anemometer
6. Earthquake: Richter scale
7. Degree of Humidity: Hygrometer
8. Blood Pressure: Sphygmomanometer
9. Radioactivity: Geiger counter
10. High Temperature: Pyrometer
11. Rainfall: Rain Gauge
12. Earthquake Recording: Seismograph
13. Electric current: Ammeter
14. Altitude: Altimeter
15. Velocity and Direction of Wind: Anemometer
16. Sensitivity of Skin: Algeismeter
17. Atmospheric Pressure: Aneriodograph/Barometer
18. Improvement of Hearing Power: Audiometer
19. Quantity of Heat: Calorimeter
20. Intensities of Colors: Colorimeter
21. Longitude of Vessel Over Sea: Chronometer
22. Detection of Electric Charge: Electroscope
23. Voltage Difference: Electrometer
24. Depth of the Ocean: Fathometer
25. Small Electric Current: Galvanometer
26. Relative Density of Liquids: Hydrometer
27. Change in Atmospheric Humidity: Hygroscope
28. Detection and Measurement of Light: Photoelectric Cell
29. Salinity of Water: Salinometer
30. Spectrum Analysis: Spectroscope
31. Hearing of Heartbeat and Lung Sound: Stethoscope
32. Maintenance of a Constant Temperature: Thermostat
33. Amplification of Current: Transistor
34. Measurement OF Potential Difference between Two Points: Voltammeter
35. Flow of Air: Aerometer
36. Radiant Energy: Radiometer
37. Conversion of rays into mechanical energy is Radiograph
38. Measurement of Intensity of Light: Lucimeter
39. The energy of food is measured in Calories
40. The microscope is used to study Small and near objects
41. The S.I unit of temperature is Kelvin
42. The telescope is used for viewing Distant Objects
43. Decibel is a unit of Sound
44. The instrument used to measure Electric Current is Ammeter
45. The apparatus used in submarines to give a clear view of the object, on the surface of the ocean or ground is known as Periscope
46. Richter Scale is used for measuring Intensity of Earthquake
47. Fathometer is used to measure Ocean Depth
48. Hygrometer is used to measure Relative Humidity
49. Venturi Tube is used for Measuring Flow of a Fluid
50. Coronagraph is used for Observing and often photographing the sun‘s corona
51. Microphone is used to convert sound waves into electric energy
52. Velocity of wind is measured by Anemometer
53. Altimeter is used to measure the approximate height above the ground
54. Light year is related to Distance
55. Pressure of gases is measured by Barometer
56. Altitude of the Sun is measured by Sextant
57. There are 981 Dynes in one gram weight
58. When listening to heart beat with stethoscope, one hears closing of valves
59. The unit of Current is Ampere
60. The unit of energy in MKS system is Joule
61. The intensity of an earthquake is measured by Seismograph
62. Centigrade and Fahrenheit scales give the same reading at -40 Degree
63. The instrument, which is used to measure temperature by radiation, is called Pyrometer
64. Centrifuge is used to separate mixtures of chemicals
65. Radio Telescope is used to receive radio waves from objects in space
66. Audiometer is used to measure intensity of sound
67. A chronometer is used to measure time
68. Electroscope detects the presence of electric current
69. Stroboscope is used to view rapidly moving objects
70. Taceometer is used to measure distance, elevations and bearings during survey
71. Retinoscope is an instrument used to determine Refractive power of lens
72. The final image produced by a simple microscope is Virtual and Erect
73. Photodiode is used for the detection of Light
74. A Polaroid is a device used for analysing polarized light
75. The spectrum of luminous bodies is studied by Spectrometer
76. Transformer is used for conversion of low voltage into high voltage and vice-versa
77. Ophthalmoscope is used to observe Retina
78. Sonar works on the principle of Absorption of sound