Which of the following pair is incorrect?
I. Parsec - Distance
II. Barrel - Liquid
III. Light Year - Time
Only III
Only I and III
Only II
All are correct
When light passes from one medium to another, this phenomenon of change in its direction is called ...............
Refraction
Diffraction
Propagation
No option is correct
In a qualitative way, the tendency of undisturbed objects to stay at rest or to keep moving with the same velocity is called .............
force
acceleration
friction
inertia
The time taken by a pendulum to complete one oscillation is called
Maximum speed
Average speed
Time period
Time interval