Answer: wavelength is 
The frequency of the microwave is, f = 2.30 GHz.
To Find frequency use the formula:
λ
Where, c is the speed of electromagnetic wave or light. f is the frequency, and λ is the wavelength of light.
Rearranging, 
Plug in the values,
Answer:
C
Explanation:
The sun has rotated causing the shadow to reflect.
Answer: q = -52.5 μC
Explanation:
The complete question is given thus;
A point charge Q moves on the x-axis in the positive direction with a speed of 280 m/s. A point P is on the y-axis at y=+70mm. The magnetic field produced at the point P, as the charge moves through the origin, is equal to -0.30uTk. What is the charge Q? (uo=4pi x 10^-7 T m/A).
SOLVING:
from the given parameters we can solve this problem.
Given that the
Speed = 280 m/s
y = 70mm
B = -30 * 10⁻⁶T
Using the equation for magnetic field we have;
Β = μqv*r / 4πr²
making q (charge) the subject of formula we have that;
q = B * 4 *πr² / μqv*r
substituting the values gives us
q = (-0.3*10⁻⁶Tk * 4π * 0.07²) / (4π*10⁻⁷ * 280 ) = - [14.7 * 10⁻¹⁰k / 2.8 * 10⁻⁵ k ]
q = -52.5 μC
cheers i hope this helped !!!
Answer:
- a change in color
- the formation of a precipitate
- the formation of bubbles
Explanation:
In a chemical reaction, there is always a rearrangement of atoms within the molecules of reactants to form new products. Such a change is different from changes in the physical form of molecules, e.g. shape.
Thus, according to this criteria, only three options are correct in the given question. A change in color is definitely an indication of chemical reaction because the emission of light before and after cannot be changed unless molecules are rearranged to form a new chemical. Likewise, precipitates form when a reaction takes place between chemically dissolved molecules to form less or not dissolvable compounds. In the end, the configuration of bubbles also indicates that the reaction has taken place because new gases are being released.
On the other hand, change in shape is a physical change because the composition doesn't need to also been changed. An example is the ice formation from water. Same is the case with "change of clear liquid to cloudy" because the addition of non-reactive substances could change the nature of liquid to cloudy however the reaction doesn't need to have taken place.
