Use kinematic equations to solve:
1) yf = yo + vo*t + 1/2at²
yf = final height
yo = initial height
vo = initial velocity
a = acceleration
t = time
yf - yo = vo*t + 1/2at²
yf - yo = h
vo = 0
Thus,
h = 1/2at²
h = 1/2(9.8)(12)² = 705.6 m
2) vf = vo + at
vo = 0
Thus,
vf = at
vf = (9.8)(12) = 117.6 m/s
The frequency of light is 3.88 x 10^22Hz.
What is electromagnetic radiation?
The electromagnetic spectrum is the area where the electromagnetic radiation that we see as light, or visible light, is found. Visible light usually has wavelengths between 400 and 700 nanometers (nm) or frequencies between 750 and 420 terahertz, which are between the longer wavelengths of infrared and ultraviolet (with shorter wavelengths).
E = 1.55 x10^13 J/ mol
E = hv
v = 1.55 x 10^13/1mol x 1mol/6.023 x )/6.626 x
velocity = 3.88x10^22 s-1
since 1 Hz = 1/ s = 1
velocity =3.88x 10^22 Hz
To learn more about Light the link is given below:
brainly.com/question/1555553
#SPJ4
Answer:
y = 20.38 [m]
Explanation:
In order to solve these problems, we must use the following kinematics equation.

where:
Vf = final velocity = 0
Vi = initial velocity = 72 [km/h]
g = gravity acceleration = 9.81 [m/s^2]
y = vertical elevation [m]
We need to convert [km/h] to [m/s]
![72[\frac{km}{h}]*[\frac{1h}{3600s}]*[\frac{1000m}{1km} ] = 20 [m/s]](https://tex.z-dn.net/?f=72%5B%5Cfrac%7Bkm%7D%7Bh%7D%5D%2A%5B%5Cfrac%7B1h%7D%7B3600s%7D%5D%2A%5B%5Cfrac%7B1000m%7D%7B1km%7D%20%5D%20%3D%2020%20%5Bm%2Fs%5D)
Note: the negative sign of the equation means that the acceleration acts in the opposite direction to the movement of the body. And the final speed is zero, because when the body reaches the maximum height, the Stone does not move its speed has been reduced to its entirety.
0 = (20)^2 - (2*9.81*y)
20^2 = 2*9.81*y
y = 20.38 [m]
Yes, you need to convert unless the question specifically requires km/h.
Answer:
The normal force acting on the block is 980 N.
Explanation:
Mass of box = 100 kg
Coefficient of static friction = 0.40
Coefficient of kinetic friction = 0.20
We need to calculate the normal force
We know that,
When the object is placed on the flat surface then the normal force is equal to the weight of the object.
So. The normal force = mass x acceleration due to gravity

Where, N = Normal force
m = mass of object
g = acceleration due to gravity


Hence, The normal force acting on the block is 980 N.