<u>In modern physics</u>, as it was called "Stefan-Boltzmann law", the total energy radiated per unit surface area of a black body is directly proportional to the fourth power of the black body's temperature T
as:

where: P is the power (total energy radiated per second per square meter) and T is the temperature of a black body.
then we can make a ratio between the state of before quadruple (with subscript 1) and after (with subscript 2) as:

As

Then

then

- The factor will the total energy radiated per second per square meter increase = 256
A. freezing, when water turns to ice the water is turning from a liquid to a solid.
Answer:
the first one is Primary
the second one I think it's Mature but I don't know
Answer:
The speed of the skier after moving 100 m up the slope are of V= 25.23 m/s.
Explanation:
F= 280 N
m= 80 kg
α= 12º
μ= 0.15
d= 100m
g= 9,8 m/s²
N= m*g*sin(α)
N= 163 Newtons
Fr= μ * N
Fr= 24.45 Newtons
∑F= m*a
a= (280N - 24.5N) / 80kg
a= 3.19 m/s²
d= a * t² / 2
t=√(2*d/a)
t= 7.91 sec
V= a* t
V= 3.19 m/s² * 7.91 s
V= 25.23 m/s
Answer:
1456 N
Explanation:
Given that
Frequency of the piano, f = 27.5 Hz
Entire length of the string, l = 2 m
Mass of the piano, m = 400 g
Length of the vibrating section of the string, L = 1.9 m
Tension needed, T = ?
The formula for the tension is represented as
T = 4mL²f²/ l, where
T = tension
m = mass
L = length of vibrating part
F = frequency
l = length of the whole part
If we substitute and apply the values we have Fri. The question, we would have
T = (4 * 0.4 * 1.9² * 27.5²) / 2
T = 4368.1 / 2
T = 1456 N
Thus, we could conclude that the tension needed to tune the string properly is 1456 N