(A) Speed of sound
(B) Density of milk
(C) Humidity of air
(D) Specific gravity of liquids
Answer: (C) Humidity of air
Q. Who invented the first hygrometer in 1783 using human hair to measure humidity?
(A) Swiss physicist Horace Benedict de Saussure
(B) German Albert Einstein
(C) Swiss physicist Kappeller
(D) None of these
Answer: (A) Swiss physicist Horace Benedict de Saussure
Q. The first crude hygrometer was invented in 1480 by:
(A) Swiss physicist kappeller
(B) Italian polymath Leonardo da Vinci
(C) Swiss physicist Albert Einstein
(D) None of these
Answer: (B) Italian polymath Leonardo da Vinci