Answer:
if Josh ate 1/4 of a pizza what's the fraction of the pizza is left
<span>The scientists use data
and measurement to obtain empirical evidence. Data can be collected through
direct observation or else experimentation. Empirical measurements and data can
be gathered by using qualitative and quantitative methods. Empirical evidence
contains the recording and analyzing the data which is a central part of scientific
method.</span>
Answer:
Convective zone, chromosphere, corona
Explanation:
A star like the Sun is divided into different layers according to pressure, density, temperature, and the mechanics of energy transport (in the case of the convective zone and radiative zone) for each of those layers.
In stars, there is an equilibrium between two forces, the force of gravity in the inward direction due to their own mass and the radiation pressure in the upward direction as a consequence of the nuclear reaction in their core, that is known as hydrostatic equilibrium.
That leads to different layers according with the properties described above.
Near the core, in the Sun, there is a radiative zone since radiation is the best mechanism of energy transport in this area. Then, in the next layer, it can be found that convection becomes a more efficient way of energy transport that radiation due to the fact that the inner part of the convection zone is at a greater temperature than the outer one.
Finally, there is the atmosphere of the Sun (chromosphere, photosphere, and corona).
Key terms:
Convection: Transport of energy due to different in density and temperature of a material (liquid, gas).
Answer:
3.6 m/s
Explanation:
From the law of conservation of momentum,
Total momentum before jump = Total momentum after jump
<em>Note: Before Dan jump off the skateboard, they where both moving with the same velocity</em>
u(m+m') = mv+m'v'................. Equation 1
Where m = Dan's mass, m' = mass of the skateboard, u = common velocity before the jump, v = Dan's final velocity, v' = The final velocity of the skateboard.
make v the subject of the equation
v = [u(m+m')-m'v')]/m.............. Equation 2
Given: u = 4.0 m/s, m = 50 kg, m' = 5 kg, v' = 8 m/s
Substitute into equation 2
v = [4(50+5)-(5×8)]/50
v = (220-40)/50
v = 180/50
v = 3.6 m/s
A) elements in the same group usually have similar chemical properties
B) This is because their atoms have the same number of electrons in the highest occupied energy shells
C) Lithium, sodium, potassium in group 1 elements are reactive metals called the alkali metals