The correct answer is C) type of medium. Electromagnetic waves travel faster in solids than in liquids, and faster in liquids than in gases.
FT=MV
F(4)=(5)(20)
F= 100/4
F= 25 N
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
The answer for the following problem is explained below.
Therefore the volume charge density of a substance (ρ) is 0.04 × C.
Explanation:
Given:
radius (r) =2.1 cm = 2.1 × m
height (h) =8.8 cm = 8.8 × m
total charge (q) =6.1× C
To solve:
volume charge density (ρ)
We know;
<u> ρ =q ÷ v</u>
volume of cylinder = π ×r × r × h
volume of cylinder =3.14 × 2.1 × 2.1 × × 8.8 ×
volume of cylinder (v) = 122.23 ×
<u> ρ =q ÷ v</u>
ρ = 6.1× ÷ 122.23 ×
<u>ρ = 0.04 × </u><u> C</u>
Therefore the volume charge density of a substance (ρ) is 0.04 × C.
True that is what a convection current is