The radio waves are electromagnetic wave, so it travels with velocity of light i.e 
.
We can use the relation between frequency, wavelength and speed as
Here c is speed of light, 
is wavelength and f is frequency and its value is given 99.90 FM, it is actually in megahertz (i.e 99.90 MHz).
Therefore,
.
Thus, the broadcast wavelength of the given radio station is 3.003 m.
Answer:
The resulting magnetic force on the wire is -1.2kN
Explanation:
The magnetic force on a current carrying wire of length 'L' with current 'I' in a magnetic field B is
F = I (L*B)
Finding (L * B) , where L = (2, 0, 0)m , B = (30, -40, 0)
L x B = ![\left[\begin{array}{ccc}i&j&k\\2&0&0\\30&-40&0\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Di%26j%26k%5C%5C2%260%260%5C%5C30%26-40%260%5Cend%7Barray%7D%5Cright%5D)
= (0, 0, -80)
we can now solve
F = I (L x B) = I (-80)
F = -1200 kmN
F = -1200 kN * 10⁻³
F = -1.2kN
The equation for potential energy is denoted as;
Pe = mgh,
where m = the mass, g = acceleration due to gravity, and h = vertical height of the apple. We are given the units for everything but height, which is also what we are solving for. We can then algebraically rearrange our initial equation to solve for h;
h = (Pe)/(mg)
Plug in your given units, and solve!
Post-check:
h = Pe/mg
h = 175J/(0.36g)(-9.81m/s^2)
h = appr. 49.5 meters
Note: Potential energy is a vector quantity; the displacement of the apple will be a negative number, but the distance itself, a scalar quantity, will be the absolute value of that.
Answer:
Explanation:
refractive index of ember = sin of angle of incidence / sin of angle of refraction
= sin 35 / sin24
= .5735 / .4067
= 1.41
This is refractive index of ember with respect to water
refractive index of ember with respect to water
= wμe = μe / μw
μe = wμe x μw
= 1.33 x 1.41
= 1.87
refractive index of ember with respect to air = 1.87 .
