Answer:
A) 72° or 71.56°
Explanation:
We have two components on the X-axis and y-axis respectively. So we can use the tangent of the angle to be able to find the angle with respect to the horizontal component.
Ax = 2.5
Ay = 7.5
tan(α) = 7.5/2.5

α = 71.56°
Answer:
1. T₁ = 500 N
2. T₂ = 866 N
Explanation:
Please see attached photo for the diagram.
Thus, we can obtain obtained the value of T₁ and T₂ as follow:
1. Determination of T₁
Angle θ = 30
Hypothenus = 100 kg
Opposite = T₁ =?
Sine θ = Opposite /Hypothenus
Sine 30 = T₁ / 100
Cross multiply
T₁ = 100 × Sine 30
T₁ = 100 × 0.5
T₁ = 50 Kg
Multiply by 10 to express in Newton
T₁ = 50 × 10
T₁ = 500 N
2. Determination of T₂
Angle θ = 60
Hypothenus = 100 kg
Opposite = T₂ = ?
Sine θ = Opposite /Hypothenus
Sine 60 = T₂ / 100
Cross multiply
T₂ = 100 × Sine 60
T₂ = 100 × 0.8660
T₂ = 86.6 Kg
Multiply by 10 to express in Newton
T₂ = 86.6 × 10
T₂ = 866 N
<span><u>Answer</u>
c). random internal motion of atoms and molecules.
<u>Explanation </u>
Diffusion is the movement of particles from a region of high concentration to region of low concentration. The rate of diffusion can be increased by increasing amount of temperature but this is not its primary cause. Diffusion is primarily caused by movement of molecules or atoms in a substances. Form the choices given, the correct answer is c. random internal motion of atoms and molecules.
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It sounds like a special relativity question but I need more info for a total answer. But remember it's length in the lab frame is
L•sqrt(1-(v/c)^2) where L is the rest length, v is its velocity magnitude and c is the speed of light. Sqrt is the square root (I'm on a phone so I can't see the math equation editor)