JEE Exam  >  JEE Questions  >  If tube length of astronomical telescope is 1... Start Learning for Free
If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objective
  • a)
    100 cm
  • b)
    10 cm
  • c)
    20 cm
  • d)
    25 cm
Correct answer is option 'A'. Can you explain this answer?
Most Upvoted Answer
If tube length of astronomical telescope is 105 cm and magnifying powe...
Given data:
Tube length of astronomical telescope = 105 cm
Magnifying power for normal setting = 20

To calculate: Focal length of objective

Formula used: Magnifying power = Focal length of objective / Focal length of eyepiece

Calculation:
Given, Magnifying power = 20
Tube length = 105 cm
Let, Focal length of eyepiece = f

Magnifying power = Focal length of objective / Focal length of eyepiece
20 = Focal length of objective / f
Focal length of objective = 20f

Now, using the formula for the total length of a telescope:
Total length of telescope = Focal length of objective + Focal length of eyepiece

105 = 20f + f
105 = 21f
f = 5 cm

Substituting the value of f in the above equation, we get:
Focal length of objective = 20f = 20 x 5 = 100 cm

Therefore, the focal length of the objective is 100 cm, which is option (A).
Explore Courses for JEE exam
If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer?
Question Description
If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer?.
Solutions for If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for JEE. Download more important topics, notes, lectures and mock test series for JEE Exam by signing up for free.
Here you can find the meaning of If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectivea)100 cmb)10 cmc)20 cmd)25 cmCorrect answer is option 'A'. Can you explain this answer? tests, examples and also practice JEE tests.
Explore Courses for JEE exam

Top Courses for JEE

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev