Unit and Measurement MCQs

Q. The moon is observed from two diametrically opposite points A and B on earth. The angle θ subtended at the moon by the two directions of observation is 1°54′; given that the diameter of the earth to be about 1.276×107m. Compute the distance of the moon from the earth. 4.5x 109 m 3.83 x108 […]

Q. A student measures the time period of 100 oscillations of a simple pendulum four times. The data set is 90s, 91s, 92s and 95s. If the minimum division in the measuring clock is 1s, then the reported mean time should be (92 ± 2)s (92 ± 5)s (92 ± 1.8)s (92 ± 3)s Answer:

Q. A student measured the length of a rod and wrote it as 3.50 cm. Which instrument did he use to measure it? Ameter scale A vernier calliper where the 10 divisions in vernier scale matches with 9 divisions in main scale and main scale has 10 divisions in 1 cm A screw gauge having

Q. The ratio of the volume of the atom to the volume of the nucleus is of the order of 1015 1025 1020 1010 Answer: 1015

Q. The damping force on an oscillator is directly proportional to the velocity. The unit of the constant of proportionality is kg-ms-1 kg-ms-2 kgs-1 kg-s Answer: kgs-1

Q. Which of the following measurement is most precise? 5.00 mm 5.00 cm 5.00 m 5.00 km Answer: 5.00 mm

Q. Amongst the following options, which is a unit of time? Light year Parsec Year None of these Answer: Year

Q. If the value of work done is 1010 g-cm2 s-2 , then its value in SI units will be 10 kg-m2s-2 102 kg-m2s-2 104 kg-m2s-2 103 kg-m2s-2 Answer: 103 kg-m2s-2

Q. The SI unit of thermal conductivity is J m-1K-1 W-m K-1 Wm-1K-1 Jm K-1 Answer: Wm-1K-1

Q. The density of a material in SI units is 128 kg m-3 . In certain units in which the unit of length is 25 cm and the unit of mass is 50 g, the numerical value of density of the material is 40 16 640 410 Answer: 40