If we select the unit of acceleration as 980cm/s2 and unit of velocity as 3x1010cm/s the unit of time will be
4.6x107s
3.6x106s
3.06x107s
4.66x107s
Which of the following is a more accurate measuring instrument?
Metre Scale
Vernier Calipers
Screw Guage
Both screw guage and vernier calipers
In an experiment the angles are required to be measured using an instrument.29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale.If the smallest division of the main scale is half - a - degree (= 0.5°), then the least count of the instrument is
one minute
half minute
one degree
half degree
Which of the following is a dimensionless quantity?
Angular Frequency
Stress
Strain
Surface tension
The most precise observation of the following is:
3426 gm
342.6gm
34.26gm
3.426 gm
The dimensional formula for thermal conductivity is
[MLT-1θ-1]
[MLT-3θ-1]
[M2LT-3θ-2]
[ML2T-2θ]
One Fermi is equal to:
10-7m
10-8m
10-15m
10-10m
The dimensional formula of potential
[ML2T-3]
[ML2T-3A]
[ML2T-2A]
[ML2T-3A-1]
In a vernier callipers, one main scale division is x cm and n divisions of the vernier scale coincide with (n -1) divisions of the main scale.The least count (in cm ) of the callipers is :
(n - 1/ n)x
nx / (n -1)
x / n
x / (n -1 )
A student measures the thickness of a human hair with the help of a microscope of magnification 100.He takes 20 readings and find average field of view of microscope as 3.5 mm.What is the thickness of the hair?
0.35 m
0.035 m
0.0035 m
none of these
