Answer:
The bohr's model is the primitive model for the hydrogen atom, comparatively to the atom of valence shell. And it is derived from the hydrogen atom of the first approximation by using the quantum mechanics.
Basically, the model state that the electron revolved around in circular orbit in atom around the central nucleus. And it can be fixed in the circular orbit at the set of discrete distance at the nucleus.
Answer:
The force parallel to the horizontal is 26.24 N
Explanation:
She pulls on the leash with a force F = 30 N, this force, since its at an angle of 29° (i will cal this angle
), it has a force component on x (the horizontal, i will call this force
) and a force component on y (the vertical, i will call this
).
This can be seen in the attached picture.
Since we are asked about the force parallel to the horizontal, we need to find the component of the force
, since
is the adjacent angle, we need to use cosine:

since
and 



The force parallel to the horizontal is 26.24 N
Compared to coffee at room temperature, the molecules of the coffee at 34°C will be moving faster and colliding with one another more frequently.
Part (a): Velocity of the snowball
By conservation of momentu;
m1v1 + m2v2 = m3v3,
Where, m1 = mass of snowball, v1, velocity of snowball, m2 = mass of the hat, v2 = velocity of the hat, m3 = mass of snowball and the hat, v3 = velocity of snowball and the hut.
v2 = 0, and therefore,
85*v1 + 0 = 220*8 => v1 = 220*8/85 = 20.71 m/s
Part (b): Horizontal range
x = v3*t
But,
y = vy -1/2gt^2, but y = -1.5 m (moving down), vy =0 (no vertical velocity), g = 9.81 m/s^2
Substituting;
-1.5 = 0 - 1/2*9.81*t^2
1.5 = 4.905*t^2
t = Sqrt (1.5/4.905) = 0.553 seconds
Then,
x = 8*0.553 = 4.424 m
When water evaporates of your body it cools you down, hence why after a shower when the water droplets begin to evaporate you feel cold