1. Answer the following questions briefly.
(a) What is the angle of inclination of the earth's axis with its orbital plane?
(b) Define rotation and revolution.
(c) What is a leap year?
(d) Differentiate between the Summer and Winter Solstice.
(e) What is an equinox?
(f) Why does the Southern Hemisphere experience Winter and Summer Solstice in different times than that of the Northern Hemisphere?
(g) Why do the poles experience about six months day and six months night?
Answers
Answer:
Answer 1.
(a) The angle of inclination of the earth’s axis with its orbital plane is 66½°.
(b) The movement of the earth on its axis is called rotation. The movement of the earth around the sun in a fixed path or an orbit is called Revolution.
(c) Every fourth year, February has 29 days instead of 28 days. Such a year with 366 days is called a leap year.
(d) Summer Solstice– When the Southern hemisphere experiences the winter season and it is summer in the northern hemisphere. At that point in time, the position of the earth on 21st June is called the Summer Solstice.
Winter Solstice– When the Southern hemisphere experiences the summer season and the reverse occurs at the Northern hemisphere. At that point in time, the position of the earth on 22nd December is called the Winter Solstice.
(e) On 21st March and September 23rd, direct rays of the sun fall on the equator. At this position, neither of the poles is tilted towards the sun. Therefore, the whole earth experiences equal days and equal nights. This is called an equinox.
(f) The Earth is always revolving and it is divided into two hemispheres. The part of the earth which faces the sun experiences summer and the part away from the sun experiences winter. Therefore, Southern Hemisphere experience Winter and Summer Solstice at different times than that of the Northern Hemisphere.
(g) The Poles experience 6 months of day and six months of nights due to the inclination of the earth on its own axis. This inclination keeps one pole towards the sun and another pole away from the sun for 6 months each. This is the reason behind this condition.
Explanation:
i hope this may helpu
Answer:
a) 23.5 degrees
b) Rotation is the movement of a body around its axis. When three-dimensional objects like earth, moon and other planets always rotate around an imaginary line, it is called a rotation axis.
The orbital motion of an object around another object is called Revolution.
c) The Earth revolves around the sun in 365 days and 4 hours . These 0.25 hours are not counted in the calendar. hence after every four years these 0.25 hours or four hours end up becoming 24 hours that constitutes a whole day. when this happens another day is added in the calendar making it 366 days. This 1 day is added in the month of February making February have 29 days. This is a leap year.
d) The summer solstice or midsummer, occurs when one of the Earth’s poles (North pole) has its maximum tilt toward the Sun.
The winter solstice occurs when one of the Earth’s poles (North Pole) has its maximum tilt away from the Sun.
e)On 21st March and September 23rd, direct rays of the sun fall on the equator. At this position, neither of the poles is tilted towards the sun. Therefore, the whole earth experiences equal days and equal nights. This is called an equinox.
f)The Earth is always revolving and it is divided into two imaginary hemispheres. The part of the earth which faces the sun experiences summer and the part away from the sun experiences winter. Therefore, Southern Hemisphere experience Winter and Summer Solstice at different times than that of the Northern Hemisphere.
g)The axis of the earth is tilted, due to which the sun continuously either shines or cannot be seen for a long time here. Although the earth rotates and day changes into night and night into day at other places, but the poles remain under the same stage for a much longer time due to the tilt.
Hope it Helps!!!