Answer:
h = 20 m
Explanation:
given.
height, h = 10 m
Potential energy at 10 m = 50 J
Kinetic energy at 10 m = 50 J
maximum height the ball will reach, H = ?
Total energy of the system
T E = 50 J + 50 J
T E = 100 J
now,
A h = 10 m
P E = m g h
50 = m g x 10
mg = 5 ..............(1)
at the top most Point the only Potential energy will be acting on the body.
now, TE = Potential energy
100 = m g h
5 h = 100
h = 20 m
hence, the maximum height reached by the ball is equal to 20 m.
Complete Question
Due to blurring caused by atmospheric distortion, the best resolution that can be obtained by a normal, earth-based, visible-light telescope is about 0.3 arcsecond (there are 60 arcminutes in a degree and 60 arcseconds in an arcminute).Using Rayleigh's criterion, calculate the diameter of an earth-based telescope that gives this resolution with 700 nm light
Answer:
The diameter is
Explanation:
From the question we are told that
The best resolution is 
The wavelength is 
Generally the
1 arcminute = > 60 arcseconds
=> x arcminute => 0.3 arcsecond
So

=> 
Now
60 arcminutes => 1 degree
0.005 arcminutes = > z degrees
=> 
=> 
Converting to radian

Generally the resolution is mathematically represented as

=> 
=>
=>
Answer:
1977.696 J
Explanation:
Given;
Weight of the box = 28.0 kg
Force applied by the boy = 230 N
angle between the horizontal and the force = 35°
Therefore,
the horizontal component of the force = 230 × cosθ
= 230 × cos 35°
= 188.405 N
Coefficient of kinetic friction, μ = 0.24
Force by friction, f = μN
here,
N = Normal force = Mass × acceleration due to gravity
or
N = 28 × 9.81 = 274.68 N
therefore,
f = 0.24 × 274.68
or
f = 65.9232 N
Now,
work done by the boy, W₁ = 188.405 N × Displacement
= 188.405 N × 30
= 5652.15 J
and,
the
work done by the friction, W₂ = - 65.9232 N × Displacement
= - 65.9232 N × 30 m
= - 1977.696 J
[ since the friction force acts opposite to the direction of motion, therefore the workdone will be negative]
Answer:
b. a lens does not focus all colors of light to the same place.
Explanation:
Chromatic aberration is a defect of a lens. In this defect, the lens is unable to focus the different wavelengths of the light on a single focal point. It is also known as chromatic distortion and color fringing. It is caused by the dispersion of light while passing through a lens. As a result, the image might become blurred and different colors are observed around its edges. It can be corrected by the use of a combination of converging and diverging lenses.
Hence, the correct option will be:
<u>b. a lens does not focus all colors of light to the same place.</u>