Answer:
The Magnifying power of a telescope is 
Explanation:
Radius of curvature R = 5.9 m = 590 cm
focal length of objective
= 
⇒
= 
⇒
= 295 cm
Focal length of eyepiece
= 2.7 cm
Magnifying power of a telescope is given by,



therefore the Magnifying power of a telescope is 
Answer:
The height reached is 20m, The time taken to reach 20m is 2 seconds
Explanation:
Observing the equations of motion we can see that the following equation will be most helpful for this question.

We are given initial velocity, u
We know that the stone will stop at its maximum height, so final velocity, v
Acceleration, a
And we are looking for the displacement (height reached), s
Substitute the values we are given into the equation

Rearrange for s



s = -20 (The negative is just showing direction, it can be ignored for now)
The height reached is 20m
Use a different equation to find the time taken

Substitute in the values we have

Rearrange for t



t = 2s
The time taken to reach 20m is 2 seconds
You want to use PEMDAS to solve this equation.
4+9*2/3-1
4+18/6-1
4+6-1
10-1
9
Your answer is 9
Thanks -John
If you have anymore question just ask! :)
Answer
given,
D = 50 mm = 0.05 m
d = 10 mm = 0.01 m
Force to compress the spring




F = 3160 N
stress correction factor from stress correction curve is equal to 1.1
now, calculation of corrected stress


= 442.6 Mpa
The tensile strength of the steel material of ASTM A229 is equal to 1300 Mpa
now,



since corrected stress is less than the
hence, spring will return to its original shape.