Given that,
Central maximum = 1 cm
Distance from the window shade to the wall =4 m
We know that,
The visible range of the sun light is 400 nm to 700 nm.
(a). We need to calculate the average wavelength
Using formula of average wavelength
Put the value into the formula
(b). We need to calculate the diameter of the pinhole
Using formula for diameter
Put the value into the formula
Hence, (a). The average wavelength 550 nm.
(b). The diameter of the pinhole is 0.537 mm.
Answer
given,
mass = 100 kg
acceleration = 10 m/s²
A mass 20 kg slides over 100 kg block
acceleration = 3 m/s²
horizontal friction exerted by the 100 kg block on 20 kg
using newton's second law
F - f = 0
F = f
f = ma
f = 20 × 3
f = 60 N
now net force acting on the 100 kg block
F_net = m a
F_net = 100 x 10
F_net = 1000 N
after 20 kg block falls the acceleration of the bock
F = 1000 +60
F = 1060 N
acceleartion on the block
a = 10.60 m/s²
Both bricks will hit the ground at the same time.
Falling vertically is always accelerating at 9.8 m/s² because of gravity.
Nothing that's happening horizontally has any effect on that.
The brick that happens to have some horizontal motion will
probably hit the ground way over there, but that will still be
at the same TIME as this one.
This is a perfect place to remind you of the old unbelievable story,
which I'll bet you heard before:
If you fire a bullet horizontally from a gun, and at the exact same
moment you DROP another bullet out of your hand next to the gun,
the two bullets will hit the ground at the same time ! Even though
they'll be far apart.
Horizontal speed has no effect on vertical behavior.
.
<h3>Explanation</h3>
The Stefan-Boltzmann Law gives the energy radiation <em>per unit area</em> of a black body:
where,
the total power emitted, 
the surface area of the body, 
the Stefan-Boltzmann Constant, and
the temperature of the body in degrees Kelvins.
.
.
.
Keep as many significant figures in as possible. The error will be large when is raised to the power of four. Also, the real value will be much smaller than 
since the emittance of a human body is much smaller than assumed.
<span>2 characteristics of stars are shown in an H-R diagram is S</span>ize and Color.
