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प्रश्न
When the planet Jupiter is at a distance of 824.7 million kilometres from the Earth, its angular diameter is measured to be 35.72″ of arc. Calculate the diameter of Jupiter
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उत्तर १
Distance of Jupiter from the Earth, D = 824.7 × 106 km = 824.7 × 109 m
Angular diameter = 35.75" = 35.72 x 4.874 x 10-6 rad
Diameter of Jupiter = d
Using the relation,
`theta = d/D`
`d = thetaD = 824.7 xx 10^9 xx 35.72 xx 4.872 xx 20^(-6)`
=143520.76 x 103 = 1.435 x 105 km
उत्तर २
Given angular diameter θ = 35.72= 35.72 x 4.85 x 10-6 rad
= 173.242 x 10-6 = 1.73 x 10-4 rad
Diameter of Jupiter D = θ x d = 1.73 x 10-4 x 824.7 x 109 m
=1426.731 x 103 = 1.43 x 108 m
संबंधित प्रश्न
Just as precise measurements are necessary in science, it is equally important to be able to make rough estimates of quantities using rudimentary ideas and common observations. Think of ways by which you can estimate the following (where an estimate is difficult to obtain, try to get an upper bound on the quantity):
the number of strands of hair on your head
Match the following.
| Column A | Column B |
| (1) Length | a. kilogram |
| (2) Mass | b. cubic metre |
| (3) Area | c. metre |
| (4) Volume | d. square metre |
Answer the following question.
Star A is farther than star B. Which star will have a large parallax angle?
Rulers, measuring tapes and metre scales are used to measure ______
Assertion (A): Distance between two celestial bodies is measured in terms of light year.
Reason (R): The distance travelled by the light in one year is one light year.
What is the length of a 100 rupee note? Guess. Now measure it using a scale.
Arbaz plans to tile his kitchen floor with green square tiles. Each side of the tile is 10 cm. His kitchen is 220 cm in length and 180 cm wide. How many tiles will he need?
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- How many cm is the length of the boundary of lake A in the drawing?(use thread to find out)
Length is a fundamental quantity.
What are the materials needed to find the length of a banana?
What formula is used to measure the area of your classroom?
Give some examples of larger length measures.
What unit will you use to measure the length of our classroom?
To measure the distance of a planet from the earth, ______ method is used.
In an experiment to estimate the size of a molecule of oleic acid 1 mL of oleic acid is dissolved in 19 mL of alcohol. Then 1 mL of this solution is diluted to 20 mL by adding alcohol. Now 1 drop of this diluted solution is placed on water in a shallow trough. The solution spreads over the surface of water forming one molecule thick layer. Now, lycopodium powder is sprinkled evenly over the film and its diameter is measured. Knowing the volume of the drop and area of the film we can calculate the thickness of the film which will give us the size of oleic acid molecule.
Read the passage carefully and answer the following questions:
- Why do we dissolve oleic acid in alcohol?
- What is the role of lycopodium powder?
- What would be the volume of oleic acid in each mL of solution prepared?
- How will you calculate the volume of n drops of this solution of oleic acid?
- What will be the volume of oleic acid in one drop of this solution?
According to the modern definition, what fraction of a second does light travel to define one metre?
Why is Earth's orbit used instead of its diameter to measure distances to stars using the parallax method?
If a planet subtends an angle α at distance D, what formula is used to find the planet's diameter?
