Fundamental Measurements in Physics

An object A is present at one vertex of an equilateral triangle. It is observed from the other two vertices of the triangle. The distance between the object and the point of observation is $100 \mathrm{m}$. What is the basis of the parallactic measurement?

Distance between the two viewpoints in parallax method is :

Parallax method is suitable for the measurement of:

Using the change in the apparent position of the object due to the viewing angle that is other than the angle that is perpendicular to the object is called _____. 

What is the uncertainty in time realisation by the cesium atomic clocks?

Which of the following is not a unit of time?

Mass spectroscope is used to measure:

At what temperature value they are measuring time units using caesium atoms?( in $°C$)

SI unit second define by how many cycles of the radiation corresponding to two energy levels of the ceasium?

What is the Internation system of unit of the time?

The mass of a box measured by a grocer’s balance is$2.300 \mathrm{kg}$. Two gold pieces of masses $20.15 \mathrm{g}$ and $20.17 \mathrm{g}$ are added to the box. What is the total mass of the
box.

The mass of a box measured by a grocer’s balance is$2.3 \mathrm{kg}$. Two gold pieces of masses $20.15 \mathrm{g}$ and $20.17 \mathrm{g}$ are added to the box. What is the total mass of the box in $\mathrm{kg}$.

Astronomical unit ($\mathrm{AU}$) is the distance between earth and the sun, $1 \mathrm{AU}$ is equal to

Convert the following from scientific to decimal notation: $5\times {10}^3$.

The dimensions of light year is -

Two identical triangular sets are used to measure the length of a rod. The division on the triangles are equally spaced. If the length of the rod is found to be $6.5\mathrm{mm}$ then calculate the division length (in $\mathrm{mm}).$

Which of the following is not a unit of time?

A person observes that the full length of a train subtends an angle of $15°.$ If the distance between the train and the person is $3 \mathrm{km},$ the length of the train, calculated using parallax method, in meters is

The nearest star to our solar system is $4.3$ light years away. The distance of this star in parsec is (Mean distance between the earth and the sun $=1.5\times {10}^{11} \mathrm{m}$ and one light year $\left.=9.46\times {10}^{15} \mathrm{m}\right)$

$1$atomic mass unit is equal to $1.67\times {10}^x \mathrm{kg}$. What is the value of $x$.