Answer:
Efriction = 768.23 [kJ]
Explanation:
In order to solve this problem we must use the principle of energy conservation. Where it tells us that the energy of a system plus the work applied or performed by that system, will be equal to the energy in the final state. We have two states the initial at the time of the balloon jump and the final state when the parachutist lands.
We must identify the types of energy in each state, in the initial state there is only potential energy, since the reference level is in the ground, at the reference point the potential energy is zero. At the time of landing the parachutist will only have potential energy, since it reaches the reference level.
The friction force acts in the opposite direction to the movement, therefore it will have a negative sign.

where:

m = mass = 56 [kg]
h = elevation = 1400 [m]
v = velocity = 5.6 [m/s]
![(56*9.81*1400)-E_{friction}=\frac{1}{2}*56*(5.6)^{2}\\769104 -E_{friction}= 878.08 \\E_{friction}=769104-878.08\\E_{friction}=768226[J] = 768.23 [kJ]](https://tex.z-dn.net/?f=%2856%2A9.81%2A1400%29-E_%7Bfriction%7D%3D%5Cfrac%7B1%7D%7B2%7D%2A56%2A%285.6%29%5E%7B2%7D%5C%5C769104%20-E_%7Bfriction%7D%3D%20878.08%20%5C%5CE_%7Bfriction%7D%3D769104-878.08%5C%5CE_%7Bfriction%7D%3D768226%5BJ%5D%20%3D%20768.23%20%5BkJ%5D)
Answer:
mm
Explanation:
As we know that

where
m represents the order of minimum
y represents the distance on the screen of the minimum from central axis
λ is the wavelength of the light
D is the distance between screen-to-slit
d represents the width of the slit
For first minima

For second minima


Answer:
1/ As a metal has higher melting point than a nonmetal has, we can guess that sample A is a metal.
2/ The melting point is over 1000 gradius Celcius: 1083 - it's not a low value. And as the sample conducts heat, it is not the element of period N3 in the periodic table, because elements in period 3 do not conduct electricity.
Explanation:
I can not see what the questions 2-3 in your picture is. I answered the question above the table: What can the student conclude about thenidentity of Sample A.
Hello.
The best answer would be A.Rift Valley.
It forms when l tectonical plates move away froem each other.
Have a nice day :)