Advertisements
Advertisements
प्रश्न
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.
पर्याय
Both A and R are true but R is not the correct reason.
Both A and R are true and R is the correct reason.
A is true but R is false.
A is false but R is true.
उत्तर
Both A and R are true and R is the correct reason.
APPEARS IN
संबंधित प्रश्न
Write true or false.
Every measurement involves two things – a number and a unit.
Exercise
Length of one’s chest can be measured using metre scale.
Guess the lengths to draw these things. Ask your friend to draw the same. After you make the drawing use a scale to measure the length. Whose drawing showed a better guess?
| Guess its length and draw |
Measure of your drawing |
Measure of your friend’s drawing |
| An ant of length less than 1 cm |
||
| Pencil of length about 7 cm |
||
| A glass 11 cm high with water up to 5 cm |
||
| A bangle of perimeter 20 cm |
||
| A curly hair of length 16 cm |
What is Dinesh’s height in metres? _____ m _____ cm.
How many stamps can be placed along its length?
How many stamps are needed to cover the rectangle?
So Anar also tried many different ways to make a boundary for 800 square meters of land.
He made rectangles A, B, and C of different sizes. Find out the length of the boundary of each. How much gold wire will he get for these rectangles?
- A
Gold wire for A = _________ metres - B
Gold wire for B = _________ metres - C
Gold wire for C = __________ metres
But then Anar made an even longer rectangle... See how long!
- D
So he will get __________ metres of gold wire!!
What is the unit of length?
Consider a sunlike star at a distance of 2 parsecs. When it is seen through a telescope with 100 magnification, what should be the angular size of the star? Sun appears to be (1/2)° from the earth. Due to atmospheric fluctuations, eye can’t resolve objects smaller than 1 arc minute.
