Answer:
when the reflecting surface is plain and without even small hurdles that are not the visible by our naked eyes. Eg : plain mirror
Explanation:
Ultravoilent rays is an type of an electromegnetic wave with wavelength 10nm .Ultraviolet wave is used by doctors in order to keep the wounds away from bacteria.
<h3>What is ultravoilent wave ?</h3>
Ultravoilent rays is an type of an electromegnetic wave with wavelength 10nm. Ultravoilent wave is directly comes frim the sun. It is classified into the UV(A) , UV(B),UV(B).
Ultravoilet rays also effects the human eyes that s why sun glasses are used. The experiments here are compared and quantified to the effectiveness of the sunscreens with various strengths.
To learn more about the ultravoilent wave refr to the link;
brainly.com/question/19706211
Answer:
I think D it could maybe B
By definition of average acceleration,
<em>a</em> = (20 m/s - 33.1 m/s) / (4.7 s) ≈ -2.78 m/s²
Vertically, the car is in equilibrium, so the net force is equal to the friction force in the direction opposite the car's motion:
∑ <em>F</em> = (1502.7 kg) (-2.78 m/s²) ≈ -4188.38 N ≈ -4200 N
If you just want the magnitude, drop the negative sign.