Answer:
44.6 N
Explanation:
Draw a free body diagram of the block. There are four forces on the block:
Weight force mg pulling down,
Normal force N pushing up,
Friction force Nμ pushing left,
and applied force F pulling right 30° above horizontal.
Sum of forces in the y direction:
∑F = ma
N + F sin 30° − mg = 0
N = mg − F sin 30°
Sum of forces in the x direction:
∑F = ma
F cos 30° − Nμ = 0
F cos 30° = Nμ
N = F cos 30° / μ
Substitute:
mg − F sin 30° = F cos 30° / μ
mg = F sin 30° + (F cos 30° / μ)
Plug in values:
mg = 20 N sin 30° + (20 N cos 30° / 0.5)
mg = 44.6 N
The radius of the cylinder is equal to half the diameter:
The volume of the cylinder is given by:
where h is the heigth of the cylinder. Converting into meters,
And the density of the material will be given by the ratio between the mass and the volume:
The area is the length times the height so A= bh ...?
Answer:
The angle of incident ray is 40°.
Explanation:
Given that the angle of incident and reflected ray are the same. In this question, we had given that both angles added up will gives you 80° so you have to divide it by 2 :
incident + reflected = 80°
Let incident = reflected = θ
θ + θ = 80°
2θ = 80°
θ = 80° ÷ 2
= 40°
Answer:
<em>the phase relationship between two waves.</em>
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Explanation:
Coherence describes all properties of the correlation between physical quantities between waves. It is an ideal property of waves that determines their interference. In a situation in which there is a correlation or phase relationship between two waves. If the properties of one of the waves can be measure directly, then, some of the properties of the other wave can be calculated.
