It doesn't rise or set. (a) Explain with the help of a diagram the phenomenon of lightning between clouds (3+2=5) and the earth. Q.70. As the Earth goes around the sun, it would cause the position of the pole star (and other stars) to move with a regular annual motion. You can use the Big Dipper to find Polaris, which is also known as the North Star… Re: Explain position of pole star over different latitudes « Reply #25 on: January 07, 2011, 09:41:06 PM » You guys obviously can't fit the FE theory around these observations and for the most part (with the exception of a PM I received) display a willful ignorance of the essence of the questions themselves. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Start studying Astronomy of the Solar System Quizes 1,2,3 & 5. A star trail is a type of photograph that uses long exposure times to capture the apparent motion of stars in the night sky due to Earth's rotation.A star-trail photograph shows individual stars as streaks across the image, with longer exposures yielding longer arcs.. Assume that the Pole Star (Polaris) is exactly in line with the Earth’s axis produced, as shown in the following diagram. 1. Q6.Give reasons for the following:- 25. Q23: Explain how you can locate pole star with the help of Ursa Major. (iv) With the help of a neat labelled diagram, explain Extend the imaginary line in North direction. OR (a) What is an earthquake? – 5 marks Q.38 Describe with the help of a diagram an instrument which can be used to detect a charged body. Describe the extraction of iron from the concentrated ore with the help of (i) a labelled diagram of the furnace used. The apparent motion of most celestial objects is from east to west, but it is possible to observe a body moving west to east, such as an artificial satellite or space shuttle that orbiting eastward. Describe natural and human activities that causes deforestation. Explain. Report ; Posted by Ranjushree Goswami 2 years, 7 months ago. Q2. In order to identify its location, the first two stars of the ‘Saptarishi Mandal’ are joined by an imaginary line which, after its extenuation, joins the Pole Star on the North Pole. CBSE > Class 08 > Science 1 answers; How can stay pole star in an one direction. Answer. Explain, why can we see full moon on a full moon day while it is not visible on a new moon day? Draw the diagram to show the position of different planets of the solar system. With the help of a diagram describe the heat zones. Explain with a diagram how you can locate pole star with the help of the constellation Great Bear (Ursa Major). The resulting phasor diagram is shown in Fig. Answer: Pole star can be located with the help of two stars at the end of Ursa Major. 0 o) the Pole Star will be in line with the horizon, i.e. Explain with a diagram how you can locate pole star with the help of the constellation Great Bear (Ursa Major). Title: Chapter 17 Solar system.pmd Author: dtpcell6 Created Date: Explain, with the help of diagram, how is moon visible to us when it does not have light of its own? These are the exception, rather than the rule, for the motion of celestial objects. Ans: Yes. In particular, they know about the north star, with its formal name of Polaris. Explain that we can see objects because they reflect light. CBSE > Class 08 > Science 1 answers; myCBSEguide. Thus, a single phase supply current is split into two phases. Report ; Posted by Wangseng Lowang 2 weeks, 2 days ago. Note. Extend this imaginary line towards the north direction. Imagine a straight line passing through these stars. Q.74. Q.68. Therefore, all the stars in the sky (except the pole star) seem to move from east to west. The Phasor Diagram of the Capacitor Start motor is shown below. Indeed, the "pole star" used by ancient Greek sailors was a different one, not nearly as close to the celestial pole. Imagine a straight line passing through these stars as shown in the figure below. Explain how it occurs. With the help of neat diagrams explain the construction of a 3-phase induction motor. This can be understood with the help of the given diagram. Q.71. set and explain each one with the help of suitable example. Trusted by 70 Lakh Students. it will have an angle of elevation or altitude of 0 o. Draw a neat diagram for a star-delta starter and explain. 22. explain the effect of rotor circuit resistance on different torques of an induction motor. (ii) necessary chemical equations representing the chemical changes occurring during the process. Pole Star is located by Ursa Major. Can we hear any sound on moon? Imagine the two stars at … Answer: No, the earth rotates on its axis from west to east. Q.72. The pole star to which the axis points now (within about one degree) used to be distant from the pole, and will be so again in a few thousand years (for your information, the closest approach is in 2017). The pole star in particular moves by about 2.1 millionth of a degree. Explain with a diagram how you can locate pole star with the help of the constellation Great Bear (Ursa Major). Q5. Discuss how the speeds of three phase induction motors can be controlled. Instead, it appears to stay put in the northern sky. With the help of diagrams on the board, explain the reflection of light. Answer: Question 7. This line is about five times the distance between two stars. Explain how you can locate the Pole Star with the help of Ursa Major. I also wanted portray how the celestial, ecliptic and galactic coordinate systems are related to each other in … Q.69. Long Answer Type Questions. – 5 marks The lung (the pump) must produce adequate airflow and air pressure to vibrate vocal folds (this air pressure is the fuel of the voice). Q.73. 3.4: The phasor diagram of a salient-pole synchronous generator. Explain with diagram any one method of starting a slip ring induction motor. In this phasor diagram, the armature current needs to be resolved into two components - one in parallel with E A How can this defect of vision be corrected ? Use diagrams on the board to explain the scattering of light. When earth rotates about its axis in a day and revolves about the Sun, the part of sky changes that can be seen. On a clear moonless sky during summer at 9.00 p.m. at the northern part of sky we can see Ursa Major. Explain with a diagram how you can locate pole star with the help of the constellation Great Bear (Ursa Major). (iii) With the help of a neat labelled diagram, explain construction and working of a auto-transformer starter used for starting 3-phase induction motor. What are the natural resources? Q4. 12. For observers in the northern hemisphere and parts of the southern hemisphere, Polaris (formally known as α Ursae Minoris because it's the brightest star in the constellation), is an important navigational aid. The vocal folds (vocal cords) are a vibrating valve that chops up the airflow from the lungs into audible pulses that … Soln: Locate the two end stars of Ursa Major. The bowl of the big dipper consists of the four bright stars. Also, the pole star just happens to be very close to the axis of the Earth's rotation. (a) (i) Explain the various parameters that influence the design of a satellite communication link. 12/04/18. – 5 marks Q.37 State the differences between eukaryotes and prokaryotes. What is deforestation? CBSE Guess having millions of pages of educational papers provided by various educational institutions, teachers and educators from India and abroad. asked Jul 27, 2018 in Science by Sakil Alam (64.0k points) stars and the solar system; class-8; 0 votes. Explain their pattern and positions in the sky. seasons. Tonight’s chart shows Polaris and the Big and Little Dippers for a September evening. Click here to download the NCERT Exemplar Class 8 Science Unit 17 Stars and Solar System Soln: For locating, the pole stars in the sky, first the big dropper or the Ursa Major constellation must be found . (b) Write any two precautions that you will take to protect yourself from lightning when you are in the playground. Some comets and small asteroids orbit the Sun in retrograde orbits. Ask: How do our rooms get light in the daytime? Explain Myopia with the help of suitable ray diagrams. Q.67. 3.4. Morning star is the name given to (a) pole star (b) star … Explain how you can locate the Pole star with the help of Ursa Major. I've been tinkering with a few diagrams in an attempt to illustrate the motion of the solar system in its journey around the Milky Way. Explain with the help of diagram how the tilt of the earth’s axis and the revolution cause. We never see the back side of moon from the eart h , Why? Explain with the help of diagram. Stars visible in the North Pole will not be visible in the South Pole. 10 Explain the operation of the following instructions in 8085 microprocessor : 3+3+4=10 (1) RRC (2) CMPR (3) LDAX Rp 4. Stargazers are familiar with the concept of the "pole star". Comment. Question 1. Q3. The final expression for the phase voltage of a salient-pole synchronous generator is as mentioned in Eq.3.8 below. Explain with a diagram how you can locate pole star with the help of the constellation Great Bear (Ursa Major). I M is the current in the main winding which is lagging the auxiliary current I A by 90 degrees as shown in the phasor diagram above. Explain with a diagram how you can locate pole star with the help of the constellation Great Bear (Ursa Major). This portal is designed to support Students and Teachers of Central Board of Secondary Education. Why pole star is stationary? We can locate the pole star with the help of Ursa Major in the following way: (i) Draw an imaginary line from the two end stars of Ursa Major. Describe the alternative sources of energy. What causes global warming? The more distant a star is, the less it appears to move. How does light help us to see things? The location of the Pole Star is fixed. What's more, the star we know as Polaris hasn't been the only North Star. Fig. 1 answer. 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