Answer:
λ₁ = 2.50 10⁻² m, λ₂ = 1.66 10⁻² m
Explanation:
Microwave communication is very efficient because it does not have atmospheric interference, for which it is widely used and has been regulated to avoid interference, the ku band is in the range between 12 and 18 GHz.
Let's calculate the wavelength for the two extreme frequencies of this band
wavelength and frequency are related
c = λ f
λ = c / f
f₁ = 12 GHz = 12 10⁹ Hz
λ₁ = 3 10⁸ /12 10⁹
λ₁ = 2.50 10⁻² m
f₂ = 18 GHz = 18 10⁹ Hz
λ₂ = 3 10⁸ /18 10⁹
λ₂ = 1.66 10⁻² m
Unfortunately in your exercise the specific frequency is not fired, for significant figures they must be the same number as the figures of the frequency, in general the frequency has 3 or 4 significant figures
C) During chemical reaction, total mass remains the same.
This is because due to the law of conservation of mass, stating that in a chemical reaction, neither mass will be created nor destroyed. So, the total mass will not change when chemical reactions occur.
F=ma
Force is 50N. Acceleration is 25 m/s^2.
50N=m*25 m/s^2
Divide both sides by 25.
mass=2 kg
If one of two interacting charges is doubled, the force between the charges will double.
Explanation:
The force between two charges is given by Coulomb's law
K=constant= 9 x 10⁹ N m²/C²
q1= charge on first particle
q2= charge on second particle
r= distance between the two charges
Now if the first charge is doubled,
we get 
F'= 2 F
Thus the force gets doubled.
