Answer:
Increase air resistance
Explanation:
Gravity forces the parachute down but air resistance pushing up on the flat surface of the parachute causes it to fall slower to the ground.
I believe it's B. the transmission of heat across matter
Answer:
ground state
Explanation:
Lets take
n=3 ,n=2 ,n=1 are the energy level.
Energy level n=1 is the ground energy level.
The energy from 3 to 1 = hν
The energy from 3 to 2 = hν₁
The energy from 2 to 1 = hν₂
We can say that
hν = hν₁ + hν₂
If the electron were de-excitation from the third level to ground level then the sum of emitted frequency will be equal to the frequency of a single electron.
Therefore the answer is ground state.
Answer: 1.59 sec
Explanation:
The kinetic energy contained in the rotation of the cylinder is 1/2 m v^2
The kinetic energy of translation is also 1/2 m v^2
so the total energy is m v^2
The force applied is mg sin (theta)
= m x 9.8 x 1/2
= 4.9 m
Now equate
F x d = m v^2
4.9 m x 3.1 = m v^2
v^2 = 4.9 x 3.1
v = sqrt(4.9 x 3.1) = 3.9 m/s
Acceleration.
V^2 = 2 a s
4.9 x 3.1 = 2 x a x 3.1
4.9 = 2 a
a = 2.45 m/s^2
Time
T = v/a
= 3.9/2.45
= 1.59 sec
Answer:
The concentration of mole evil at oxygen on that day is 0.00858 mol/L
Explanation:
Here, we want to calculate the concentration of molecular oxygen
The pressure on that day is 1.0 atm
Since oxygen is at a concentration of 21%, the pressure of oxygen will be 21/100 * 1 = 0.21 atm
Now let’s calculate the concentration;
From Ideal gas law;
PV = nRT
This can be written as;
P/RT = n/V
The term n/V refers to concentration;
Let’s make substitutions now;
P = pressure = 0.21 atm
R = molar gas constant = 0.0821 L•atm/mol•k
T = temperature = 25 = 25 + 273.15 = 298.15 K
Substituting these values, we have;
n/V = C = 0.21/(0.0821 * 298.15) = 0.00858 mol/L
