Download Which month has larger and smaller day time?

ACTIVITY-1
Which month has larger and smaller day time?
Problem: Which month has larger and smaller day time?
Aim: Finding out which month has larger and smaller duration of day in the Year
2006.
Format for Observation Table
Tools: Wall calendar mentioning
sunrise and sunset time.
Procedure: To do the experiment
fallow the below procedure.
1. Get the calendar which shows
sunrise and sunset time for each day
of the year.
2. Fill the observation table with the
time of Sunrise and Sunset.
Theory: There are
countable reasons for larger and
smaller duration of the day and
night. Some of them are: (i) Earth
rotate on its axis (ii) Earth’s axis of
rotation is not exactly vertical (iii)
Earth is spherical in shape and hence
observers position on the globe is
not same for all etc. All these
reasons give rise to the difference
in length of the day and night.
ACTIVITY-2
Path of the Sun in the Sky
Aim: Tracing out path of the Sun in the Sky.
Tools: Comparatively dark room, Calendar and Watch.
Procedure: To do the experiment follows the procedure below.
1. Find the room having window/door facing the sun.
2. Make the room darker by closing the doors and windows but keep a small portion of the window open
through which sunlight can come. (Better through a small hole).
3. If your window is glass window then get a black paper of the size of window and make a small hole
through which sunlight can come. Now paste this dark paper on the window.
4. Allow sunlight to come through the hole in the form of beam that can fall on the floor. 5. Set the time in
the watch (this will remain same for all observation dates in future days, preferable time could be 1200
hrs).
6. Mark the beam position on the floor as shown in figure 1. Now repeat the procedure for all the
observation dates.
Theory:
If you observe the sun in the sky quite frequently then you will observe that the sun’s position is not same
everyday. It goes on changing. Of course it is true that the sun is not moving but it is the Earth! In reality
what we observe is the sun’s changing position throughout the year.
Observation Table
Result :
Draw the figure of traced marking available on the floor. Now connects all the points with free
hand (smooth curve).
ACTIVITY-3
What are Dakshinayan and Uttarayan?
Aim: Understanding the Dakshinayan (Sun’s declination to South) and Uttarayan
(Sun’s declination to North).
Tools: 1 meter stick, Calendar and Watch.
Procedure: To do the experiment follows the procedure
below.
1. Locate the plane surface from where you can see the
Sun without any obstacle.
2. With the help of magnetic compass mark the SouthNorth line on the ground and furthermore EastWest line; crossing each other in an exact proportion.
This will make 4 quadrants as shown in figure below.
3. Fix meter stick exactly at the intersection of these
lines i.e. at the origin (point O). Be sure that the stick is Direction at observation location &
exactly perpendicular to the plane surface. You can use
Shadow length
plumb line to see the exact verticalness of the stick.
4. Fix the day time observation which is to be constant for all the year.
5. Shadow of the stick will fall in any one of the quadrants made earlier.
6. Mark the tip of the shadow as a point in the quadrant.
7. Mark such points for four dates in the year. For more details look at the observation table.
Theory
Ayan means movement. Dakshinaya and Uttarayan indicate the Sun’s movement to South and North
respectively. The correct definition is the sun’s declination to North or South. Since the earth’s axis is tilted
by 23 ½ degree, the sun appears more to the north for 6 months and to the south for rest of the 6 months
in a year. This is the reason that we experience winter in the northern hemisphere and summer in the
southern hemisphere at the same time e.g. Australia is cold and India is hot at same time.
Sun reaches its maximum to the south (South declination) on 21 December and to the north (North
declination) on 21 June. These are called Winter and Summer Solstices respectively. These dates may
vary with ±1 or ±2 days.
Observation Table
Time of Observation: 8:00 AM (You can fix up any day
time!)
Result :
Draw the figure similar to what you observed at your observation location.
ACTIVITY-4
Phases Of The Moon
Aim: Understanding the phases of the Moon
Tools: Notebook, pencil, eraser etc
Procedure: To do the experiment follows the procedure as given below :1. Select the Full moon day from your calendar.
2. Start observing moon’s phase in the night sky.
3. Draw the phase of the moon in observation table as you
see in the night sky.
4. Go on repeating the drawing as mentioned in the
observation table.
5. Complete the observation table.
Theory:
Moon is the natural satellite of Earth. And hence, moon revolves around the Earth. As shown in the
diagram below, the new moon occurs when the moon is positioned between the earth and sun. The
three objects are in approximate alignment. The entire illuminated portion of the moon is on the back
side of the moon, the half that we cannot see.
At a full moon, the earth, moon, and sun are in approximate alignment, just as the new moon, but the
moon is on the opposite side of the earth, so the entire sunlight part of the moon is facing us. The
shadowed portion is entirely hidden from view.
The first quarter and third quarter moons (both often called a “half moon”), happen when the moon is at
a 90 degree angle with respect to the earth and sun. So we are seeing exactly half of the moon
illuminated and half in shadow.
Once you understand those four key moon phases, in between should be fairly easy to visualize, as the
illuminated portion gradually transit between them.
Observation Table
Result:
1. After ………. days we saw the Full
moon again.
2. On 15/16th day after Full Moon we
saw …….. Moon.
(Full/Half/New)
3. The night when you could not see
the Moon is
called …………
ACTIVITY-5
Distance of The Sun in Terms of Light Minutes
Aim: Determining the distance of the Sun in light minutes.
Tool: Pen and notebook.
Theory: If somebody asks you how far is your school from your home? Then, probably you will give the
answer like 1 km, 5 km or could be of 10 km or so. If you have been to other city (may be at your
relatives) and somebody asks you how far is the city/ town from your place? Then, the answer could be of
the order of 2 km to of 3000 km! (if you both are within the India). By chance, if you met a friend from
abroad and asked how far is your city from here? Then, probably he may not give the answer in kilometers
but he may say that it takes about 8 hrs by plane! For a second you may be stuck a bit! But if you know
the average speed of the plane then probably you may calculate the rough estimate of the distance.
In astronomy, the objects like sun, stars, galaxies etc can not be figured out in such simpler way! This is
obvious, because all such objects are beyond finger countable limits. And hence it is required to use other
units for measuring the distances. The basic unit in astronomy is light year. In this activity we will find the
distance of Sun in light minutes.
The one light year (ly) is a distance that light can travel in one year.
Now question comes what is speed of light? The speed of light is 3, 00,000 KM/Sec i.e. 3 lacks kilometer per second. So let us calculate the one light year distance: 1 year will have how many seconds?
=> 60X60X24X365 = 3,15,36,000 seconds and hence; 1 ly =3,00,000 X 3,15,36,000=
~95,00,00,00,00,000 KM or we can write as 1 ly =9.5 X 1012 KM
This implies that if the object is at 1 ly distance then it is at 9.5 X 1012 KM away from us! Vis-à-vis, if the
object is at 9,500,000,000,000 KM away from us then light will take one year to reach us!
Calculation:
Now calculate the distance of sun in Light minutesData given:*The sun is at 14,95,97,900 KM
*One ly is 9.5X 1012 KM
* Light travels 3,00,000 KM in a second
Calculate answer.
ACTIVITY-6
Composition of different colors in the Sunlight
Objective: Understanding how many colors sunlight have.
Material required: prism, pen and notebook.
Procedure:
1. Arrange comparatively darker room.
2. Allow very small sunlight to pass in the room; may be through hole.
3. Put the prism across the sunlight.
4. Now look at the darker region of room.
5. You will see the different colors of sunlight.
6. Note down the colors that you have seen.
Explanation:
The observed sun light always look yellowish in color that is because sun emits maximum light in yellow
wavelength/ frequency such light is called as white light. But actually white light is not a single wave length/
frequency in nature, it is a combination of all seven colors viz. red, orange, yellow, green, blue, indigo and
violet.
As shown in figure
To conform this, one has to perform above experiment.
One can also see the different colours of light on a Compact Disk used in computers made out of very tiny
magnetic strips/ grooves whose size is in micron. When sunlight falls on the CD or on this strips/grooves
sunlight is get diffracted in different wavelength/frequency and hence we see the different wavelength lights
as different colors. Please remember CD can not be prism which can give large angle diffraction.
Observations:
1. Write the colors that you have seen.
Ans:
2. Write the colors in a sequence; as they appeared.
ACTIVITY-7
Observation on full moon days – why we see only
one side of the moon?
Aim: Observation of Moon on every Full moon day.
Apparatus: Telescope, calendar, drawing paper, pen/pencil
Procedure: Do the following:
1. With the help of calendar, locate any approaching Full moon day.
2. Note the date of observation.
3. Point the telescope towards Moon.
4. Observe the moon thoroughly.
5. Try to draw an image of Moon in the observational table.
6. If you are good enough for taking the photographs through the telescope then capture the photograph of
Moon.
7. Follow the above procedure for next few Full moon days and draw the image of Moon or take the
photographs.
Theory:
Astronomical objects revolve around its parent object e.g. Moon revolve around Earth, Earth revolves
around Sun, Sun revolves around center of galaxy etc. While most of them rotate on its axis. This holds
true for Earth and Moon as well. Earth rotates around its axis and takes 24 hours to complete one rotation.
The fact is true for Moon as well! i.e. Moon rotates on its axis at same rate within 24 hours . Therefore,
Moon being a natural satellite revolve around the Earth, hence we see only one side of the Moon all time
from Earth. The only way to see the other side of moon is to send a space probe that can fly to other side
of the moon.
Result:
Are the images/photographs same? If yes, why?
Ans:
What you understood from this experiment?
ACTIVITY-8
How to locate your Geographical Northy?
Activity 9: How to make your own magnetic compass?
Activity 10: How to find your longitude?
Activity 11: How to find the Pole Star?
Activity 12: How to make your astrolabe?
Activity 13: How to find the latitude of your place?
Activity 14: Understanding the rising and setting of Star?
Activity 15: Understanding the phases of moon?
Activity 16: Understanding the time of Moonrise?
17: Observation
Observation of
of Full
full Moon?
Activity 17:
moon?
Activity18:
18:Making
MakingSolar
SolarProject?
Project
Activity
Activity 19: How to find the angular size of Sun and Moon?
Activity 20: Understanding the angular separation?
Activity 21: How to identify the constellations?
Transit of Venus, 6 June 2012
Measurement of apparent size of Sun and Venus from Earth
Required Material and Equipment:
1. A telescope (given)
2. A Solar shade
3. A drawing board
4. A graph paper (8a)
5. Observation sheet for data (8b)
6. Pencil
Solar shade
Setting up the Telescope
Point the telescope towards the sun and get the projected image of the Sun on the graph paper. NEVER
LOOK AT THE SUN THROUGH THE TELESCOPE. The image can be made smaller or bigger, by moving the
screen closer or further from the eyepiece. Adjust it such that the image of the sun just fits the circle
on the graph sheet (8a). .
Marking Sun and Venus on the graph paper.
1. Once Image is on the graph paper mark the outer limit of the image of the Sun with pencil.
2. Draw the image of Venus on graph sheet with pencil
3. Count the number of squares along the diameter of the Sun (use observation table).
4. Count the number of squares along the diameter of the Venus (use observation table).
5. Repeat the steps 2, 3 & 4 for at least fives times.
Complete the observation table (8b) and follow the steps therein.
8
Transit of Venus, 6 June 2012
Graph paper for measurement of apparent size of the Venus and Sun
Name of Observer:...........................................................
Instrument Used (telescope):...........................................
School/Organisation:.......................................................
.........................................................................................
.........................................................................................
Place:.........................
Longitude:.................
Latitude.....................
Date:
Time:
8a
Transit of Venus, 6 June 2012
Observation Table for measurement of apparent size of the Venus and Sun
S No.
Time
Diameter of Sun in mm (Sd)
Diameter of the Venus in mm (Vd)
a
b
c
d
e
Average diameter of Sun in mm = Sd = a+b+c+d+e =
5
Average diameter of the Venus in mm = Vd = a+b+c+d+e =
5
From Earth the relative size of Sun and Venus = Sd/Vd =
Name of Observer:...........................................................
Equipment........................................................................
School/Organisation:.......................................................
.........................................................................................
.........................................................................................
Place:.........................
Longitude:.................
Latitude.....................
Date:
Time:
8b