Answer:
The railroad tracks are 13 m above the windshield (12 m without intermediate rounding).
Explanation:
First, let´s calculate the time it took the driver to travel the 27 m to the point of impact.
The equation for the position of the car is:
x = v · t
Where
x = position at time t
v = velocity
t = time
x = v · t
27 m = 17 m/s · t
27 m / 17 m/s = t
t = 1.6 s
Now let´s calculate the distance traveled by the bolt in that time. Let´s place the origin of the frame of reference at the height of the windshield:
The position of the bolt will be:
y = y0 + 1/2 · g · t²
Where
y = height of the bolt at time t
y0 = initial height of the bolt
g = acceleration due to gravity
t = time
Since the origin of the frame of reference is located at the windshield, at time 1.6 s the height of the bolt will be 0 m (impact on the windshield). Then, we can calculate the initial height of the bolt which is the height of the railroad tracks above the windshield:
y = y0 + 1/2 · g · t²
0 = y0 -1/2 · 9.8 m/s² · (1.6 s)²
y0 = 13 m
Answer:
2nd bscause there is a reaction
Well the options r not well described anyways, the answer goes:
1) Foods rich in carb, sugars, proteins...
2) Lack of activity/exercise
3) Not proper use of medicines
4) Imbalanced hormone
5) Dehydration
6) Stress (in some situations)
7) High intake of unhealthy beverages (i.e, juices, alcohol & alike)
And much more
Hope this was helpful :)
Answer:
#_photon = 7 10²¹ photons
Explanation:
Let's look for the power that affects the panel of area of 1.5 m2
I = P / A
P = I A
P = 1.37 10³ 1.5
P = 2,055 10³ W
P = E / t
If we use t = 1 s
E = P t
E = 2,055 10³ J
This is the power that the panel receives, let's look for the energy of a photon
E = h f
c = λ f
f = c /λ
E = h c /λ
Let's calculate
E₀ = 6.63 10⁻³⁴ 3 10⁸/680 10⁻⁹
E₀ = 2.925 10⁻¹⁹ J
In one second the total energy is the number of photons for the energy of each one
E = #_photon E₀
#_photon = E / E₀
#_photon = 2,055 10³ / 2,925 10⁻¹⁹
#_photon = 7 10²¹ photons
