Dimensional Formulas and Significant Figures

Study Notes

Dimensional Formulas and Significant Figures

The viscosity of oil can be described by the formula η = (P(r-x)^2) / (4vl). The dimensional formula for viscosity (η) is [ML^-1T^-1].
Derived units are units of physical quantity that can be expressed as a combination of fundamental physical quantities.
Angular momentum has the dimensional formula [ML^2T^-1].
The dimensional formula [ML^2T^-2] represents moment of force.
The velocity of light in vacuum is a dimensional constant as its value remains constant regardless of the frame of reference.
The units of the constant of proportionality for damping force on an oscillator are [kgs^-1].
The dimensional formula for (ABCD) in the expression y = A sin (Bx + Ct + D) is [M^0L^0T^0].
Strain is a dimensionless quantity.
Power has the dimensional formula [ML^2T^-3].
The solid angle subtended by the periphery of an area 1cm^2 at a point situated symmetrically at a distance of 5 cm from the area is 4 x 10^-2 steradians.
If the speed of light in vacuum is unity, the distance between the Sun and the Earth in terms of the new unit is 500 units.
Torque has the dimensions [ML^2T^-2].
Torque and potential energy have the same dimensions.
Rounding off 2.745 and 2.735 to 3 significant figures gives 2.75 and 2.74 respectively.
The number 900.06 has 5 significant digits.
The numbers 4.8000 x 10^4 and 48000.50 have 5 and 7 significant figures respectively.
Kinetic energy has the same dimensions as work.
The density of a body with mass 4.237g and volume 2.5 cm^3 is 1.7 g cm^-3.
The number 8.1000 has 5 significant digits.
If momentum (P), area (A) and time (T) are taken as fundamental quantities, then energy has the dimensional formula [P^1A^1/2T^-1].
Hubble's constant has the dimension of [T^-1].
Coeffcient of viscosity has the dimensions [ML^-1T^-1].
Physical quantities are measurable properties of a system or object.