Parallax Method

Q.

Give some examples of universal truth.

Q. Calculate the parallax of a star (in $\text{sec}$) at the distance of $4.29$ light years when viewed from two locations of earth six months apart in its orbit around the sun. Answer upto 2 places of decimal ( Assume diameter of earths orbit around sun to be $3\times {10}^{11}\text{m}$)

Q.

Explain the parallax method for measuring the distance of a near star.

Q.

Describe the Parallax method to find out how far a star is?

Q. The length of a linear rod is measured as 100.1 cm, the approximate error in the measurement is

Q.

Colour of shining bright star is an indication of its

1. Temperature

2. Mass

3. Distance from the earth

4. Size

Q. A star is $1.45parsec$ light years away. How much parallax would this star show when viewed from two locations of the earth six months apart in its orbit around the sun?

1. $2Parsec$
2. $0.725Parsec$
3. $1.45Parsec$
4. $2.9Parsec$

Q. The sun's angular diameter is measured to be ${1920}^{\prime \prime }$. The distance of the sun from the earth is $1.496\times {10}^{11}m$. What is the diameter of the sun?

1. $1\times {10}^{9}m$
2. $1.39\times {10}^{9}m$
3. $13.9\times {10}^{9}m$
4. $139\times {10}^{9}m$

Q.

Match the values of Unit in left column with magnitude in right column

Column 1	Column 2
Parsec	${10}^{-10}m$
Light year	$1.496\times {10}^{11}m$
Astronomical unit	${10}^{-15}m$
Micron	$3.086\times {10}^{16}m$
Angstrom	$9.467\times {10}^{15}m$
Fermi	${10}^{-6}m$

Q.

What is Coriolis Effect?

Q.

The capillaries shown in figure. have inner raii 0.5 mm, 1.0 mm and 1.5 mm respectively. The liquid in the beaker is water. Find the heights of water level in the capillaries. The surface tension of water is $7.5\times {10}^{-2}N{m}^{-1}$.

Q.

An asteroid is going to hit the Earth. To calculate its distance it is observed from 2 diametrically opposite points A, B on Earth. The angle subtended at the asteroid by these two directions of observations is $2^o$. Given the diameter of Earth to be about $1.276\times {10}^7$ m. compute the distance of the asteroid.

1. none of these

2. 

3. 

4. 

Q.

A star has a parallax angle p of 0.723 arcseconds. What is the distance of the star?

1. 3.38 parsecs
2. 1.38 parsecs
3. 4.38 parsecs
4. 2.38 parsecs

Q. What is parallax? Explain.

Q. To minimise parallax error, the observer should place the object :

1. as near to the scale of the ruler as possible and the eye must be directly above the scale
2. as far to the scale of the ruler as possible and the eye must be directly above the scale
3. as near to the scale of the ruler as possible and the eye must be to the right of the scale
4. as near to the scale of the ruler as possible and the eye must be to the left of the scale

Q. how to take VERNIER SCALE READING and find length of object ?

Q. A dip needle lies initially in the magnetic meridian when it shows an angle of dip $\theta$ at a place. The dip circle is rotated through an angle $x$ in the horizontal plane and then it shows an angle of dip $\theta .$ Then $\frac{\tan \theta }{\tan \theta }$ is

1. $\frac{1}{\cos x}$
2. $\frac{1}{\sin x}$
3. $\frac{1}{\tan x}$
4. $\cos x$

Q. How many light year away, the Sun is located from the galatic centre?

1. 15, 000
2. 22.5
3. 30, 000
4. 250

Q. Distinguish between the terms precise and and accuracy of a measurement. In tabular format.

Q. The moon is observed from two diametrically opposite points on earth. The angle subtended at the moon by the two directions of observations is $1^o{54}^{\prime }$. Given the diameter of the earth to be about $2.276\times {10}^{7}m$, compute the distance of moon from the earth.

1. $1\times {10}^{8}m$
2. $6.84\times {10}^{8}m$
3. $38.4\times {10}^{8}m$
4. $6.84\times {10}^{10}m$

Q. Assertion :Parallax method is used for measuring distances of nearby stars only. Reason: With increase of distance of star, parallactic angle becomes too small to be measured accurately.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. If $\overrightarrow{A}.\overrightarrow{B}=\frac{1}{2}AB$, what is the angle between $\overrightarrow{A}and\overrightarrow{B}$?

1. 
2. 
3. 
4. zero

Q. Which method is used by astronomers to calculate how far the star is?

1. Purplex
2. Parallax
3. Equillax
4. None

Q. The Sun's angular diameter is measured to be $1920$. The distance D of the sun from the earth is $1.496\times {10}^{\prime \prime }$m. find the diameter of the sun?

Q. Light year is the unit of the

1. time
2. distance
3. speed
4. intensity of light

Q.

In parallex method, we observe a star at a particular point from earth, till the time we reach diametrically opposite point on earth's orbit does that star remain at that point and at second observation there are too many stars how do we came to know, which star we measured before?

Q. Parallax method is suitable for the measurement of:

1. ball
2. planet
3. vehicle
4. distance between cities

Q. What is the approximation made in the parallax method?

1. All distances measured between two points on earth is zero.
2. All distances measured between two points on earth is constant.
3. Distance between a point on the earth and the planet is very large as compared to the distance between two points on earth's surface.
4. No approximation is made.

Q. Which one of the following methods is used to measure distance of a planet or a star from the earth?

1. Echo method
2. Parallax method
3. Triangulation method
4. None of these

Q. If a star is $5.2\times {10}^{16}m$ away. What is the parallax angle in degrees?

1. $0.67\times {10}^{-4}$ degrees
2. $1.67\times {10}^{-4}$ degrees
3. $2.3\times {10}^{-4}$ degrees
4. $1.67\times {10}^{-5}$ degrees