As the box is moving with a constant velocity, the two forces acting on the box are canceling each other.
Then friction force = 80 Newtons but in the opposite direction.
Friction force = Mu * Normal force exerted by ground = Mu * weight of box
So we find Mu.
Mu = coefficient of friction between box and horizontal surface
= Force of friction / weight = 80 / 50 * 9.81 = 0.163
When an identical box is placed on top, the force of friction is
= Mu * total weight = 0.163 * (50+50) * 9.81 = 159.9 Newtons
Answer:
It looks yellow because that is the only (major) color reflected.
Visible spectra is from about 4000-7000 Angstroms (10^-10 m).
Red are longer wavelengths and blue are the shorter wavelengths.
The Sodium doublet (yellow) occurs around 5900 Angstroms.
Sound source is at rest, you are moving with velocity v, f = frequency, c = speed of sound:
f = f0(1 + v/c)
115 = 100(1 + v/343)
115 = 100 + 100v/343
15 = 100v/343
v = 15*343/100
<span>
v = 51,45 m/s </span>
1)Kenetic Energy is defined as energy which a body possesses by virtue of being in motion. 2)KE) is KE = 0.5 x mv2. Here m stands for mass, the measure of how much matter is in an object, and v stands for the velocity of the object, or the rate at which the object changes its position..
And I hope this helped :)
