121. Who discovered hydrogen?
A. Joseph Priestley
B. Henry Cavendish
C. Humphry Davy
C. Dmitri Mendeleyev
122. Who built the first fully practical airplane?
A. Henry Ford
B. Wibur And Orville Wright
C. Alber Einstein
D. Thomas Edison
123. Calculating machine is associated with?
A. Pascal
B. Newton
C. Franklin
D. None Of These
124. Who invented typewriter?
A. J.H. Van Tassel
B. Wilhelm K. Roentgen
C. P.T. Farnsworth
D. A.H. Taylor And Leo C. Young
125. Who among the following evolved the concept of relationship between mass and energy?
A. Einstein
B. Planck
C. Daiton
D. Rutherford
126. Which instrument is used to measure the gas pressure?
A. Manometer
B. Magnometer
C. Barometer
D. Microphone
127. Which instruments is used to measure the high temperatures?
A. Potentiometer
B. Pipette
C. Psychromter
D. Pyrometer
128. Which instrument is used to measure atmospheric pressure?
A. Barometer
B. Eratosthenes
C. Thermostat
D. Viscometer
129. Which instrument is used for measuring humidity of air ( atmosphere )?
A. Hygrometer
B. Hydrophone
C. Hydrometer
D. Heliscope
130. Which instrument is used for measuring the specific gravity of liquids?
A. Hygrometer
B. Hydrophone
C. Hydrometer
D. Heliscope
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