Answer:
f=8.219*10^{8}Hz
Explanation:
We are going to use the formula v=fλ
Where v= velocity of radio waves
f= frequency
λ= wavelength of wave
- radio waves are electromagnetic waves and as such they have the speed of light which is 3*10^{8}m/s.
- also when a wave travels from one medium to another, the wavelength changes while the frequency remains the same.
- calculating for the frequency of the wave in air also gives us the frequency in the window glass.
f=\frac{v}{λ}
v=3*10^{8}m/s.
λ=36.5 cm = 36.5/100= 0.365m
f=\frac{3*10^{8}m/s.}{0.365m}
f=8.219*10^{8}Hz
This problem has three questions I believe:
>
How hard does the floor push on the crate?
<span>We have to find the net
vertical (normal) Fn force which results from Fp and Fg.
We know that the normal component of Fg is just Fg, which is equal to as 1110N.
From the geometry, the normal component of Fp can be calculated:
Fpn = Fp * cos(θp)
= 1016.31 N * cos(53)
= 611.63 N
The total normal force Fn then is:
Fn = Fg + Fpn
= 1110 + 611.63
=
1721.63 N</span>
> Find the friction
force on the crate
<span>We
have to look for the net horizontal force Fh which results from Fp and Fg.
Since Fg is a normal force entirely, so we can say that the
horizontal component is zero:
Fh = Fph + Fgh
= (Fp * sin(θp)) + 0
= 1016.31 N * sin(53)
=
811.66 N</span>
> What is the minimum
coefficient of static friction needed to prevent the crate from slipping on the
floor?
We just need to compute the
ratio Fh to Fn to get the minimum μs.
μs = Fh / Fn
= 811.66 N / 1721.63 N
<span>=
0.47</span>
Answer:
B.It is a satellite that collects data about rain and snow
C.Its orbit covers 90 percent of Earth’s surface
F.The sensors measure microwaves
Answer:
Explanation:
The centripetal acceleration is given by:
Here v is the linear speed and r is the radius of the circular motion. v is defined as the distance traveled to make one revolution (
) divided into the time takes to make one revolution, that is, the period (T).
Replacing (2) in (1) and replacing the given values:
Answer:
Option b
Explanation:
Metamorphism is the process where the variation of the geological texture resulting from the different arrangement of the minerals or the variation of minerals in protoliths, i.e., pre- existing rocks take place such that there occurs no change in state of the protolith, i.e., it does not melt into magma.
The change takes place as a result of the presence of chemically active fluids, heat and pressure.
There is a reaction between the chemically active fluid and the rock through which it passes and promotes the movement of the dissolved ions of silicate and promotes the growth of the mineral grains.
