81.
The unit of energy in MKS system is

82.
One light year is equal to

83.
Parsec is the unit of

84.
One nanometer is equal to ________ meters.

85.
The Length of the Day is determined in

86.
Which of the following pairs of physical quantities have the same dimensions?

87.
What is the fundamental unit of amount of a substance?

88.
The motion of a body that repeats itself after a regular interval of time is

89.
Negative acceleration is in the opposite direction of:

90.
If an object moves with constant velocity,