# Angular displacement and angular velocityWatch

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#1
A telescope gives a clear view of a distant object when the angular displacement b/w the edges of the object is 9.7x10^-6.
The moon is approximately 3.8km from the earth. Estimate the minimum diameter of a circular crater on the Moon's surface that can be seen using the telescope.

Thanks 😊
0
3 weeks ago
#2
Use Newton‘s gravitation equation to find the force acting between the Earth and the Moon. Sub this value into the equation for centripetal force (in terms of m, w, and r) and rearrange to find r. Then multiply that by 2.

Never seen a question like this, but this is my best guess. Good luck!
0
3 weeks ago
#3
Use Newton‘s gravitation equation to find the force acting between the Earth and the Moon. Sub this value into the equation for centripetal force (in terms of m, w, and r) and rearrange to find r. Then multiply that by 2.

Never seen a question like this, but this is my best guess. Good luck!
0
2 weeks ago
#4
(Original post by Abdullah11145)
A telescope gives a clear view of a distant object when the angular displacement b/w the edges of the object is 9.7x10^-6.
The moon is approximately 3.8km from the earth. Estimate the minimum diameter of a circular crater on the Moon's surface that can be seen using the telescope.

Thanks 😊
Is that a value you've calculated?

realistic values for the earth - moon distance are between approx 350000km and 410000km

question also appears to be about angular resolution (i.e. optics) and not angular velocity
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#5
(Original post by Joinedup)
Is that a value you've calculated?

realistic values for the earth - moon distance are between approx 350000km and 410000km

question also appears to be about angular resolution (i.e. optics) and not angular velocity
No it's about angular displacement and its located in the circular motion's chapter
0
2 weeks ago
#6
OK, you'd have to work out what the short side of a triangle with 2 long sides measuring 3.8km and a small angle of 9.7x10^-6.(units?) is.
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#7
(Original post by Joinedup)
OK, you'd have to work out what the short side of a triangle with 2 long sides measuring 3.8km and a small angle of 9.7x10^-6.(units?) is.
It's answer is 3.7 km so I guess by using formula arc=A.displacement * distance between earth and moon.
S=3.8*10^5 * 9.7x10^-6= 3.7 km
0
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