Answer:
2m₁m₃g / (m₁ + m₂ + m₃)
Explanation:
I assume the figure is the one included in my answer.
Draw a free body diagram for each mass.
m₁ has a force T₁ up and m₁g down.
m₂ has a force T₁ up, T₂ down, and m₂g down.
m₃ has a force T₂ up and m₃g down.
Assume that m₁ accelerates up and m₂ and m₃ accelerate down.
Sum of the forces on m₁:
∑F = ma
T₁ − m₁g = m₁a
T₁ = m₁g + m₁a
Sum of the forces on m₂:
∑F = ma
T₁ − T₂ − m₂g = m₂(-a)
T₁ − T₂ − m₂g = -m₂a
(m₁g + m₁a) − T₂ − m₂g = -m₂a
m₁g + m₁a + m₂a − m₂g = T₂
(m₁ − m₂)g + (m₁ + m₂)a = T₂
Sum of the forces on m₃:
∑F = ma
T₂ − m₃g = m₃(-a)
T₂ − m₃g = -m₃a
a = g − (T₂ / m₃)
Substitute:
(m₁ − m₂)g + (m₁ + m₂) (g − (T₂ / m₃)) = T₂
(m₁ − m₂)g + (m₁ + m₂)g − ((m₁ + m₂) / m₃) T₂ = T₂
(m₁ − m₂)g + (m₁ + m₂)g = ((m₁ + m₂ + m₃) / m₃) T₂
m₁g − m₂g + m₁g + m₂g = ((m₁ + m₂ + m₃) / m₃) T₂
2m₁g = ((m₁ + m₂ + m₃) / m₃) T₂
T₂ = 2m₁m₃g / (m₁ + m₂ + m₃)
A form of energy resulting from the existence of charged particles (such as electrons or protons), either statically as an accumulation of charge or dynamically as a current.
As the hard disk makes 360 revolutions per second, so one full rotation requires 1/360 sec = 0.002778 sec = 2.778 ms.
On average, however, we expect to require half a rotation. Therefore, we need 1.389 ms. The second part of the movement depends on the seek time which is 10 ms. Therefore, the total time is 1.389+10=11.389 ms on average.
Answer:
When you use your control remote, you can see that there is not a "material" thing that comes out of the control remote and goes to the TV, but there is actually energy that comes from the control remote (and this is why your control remote needs battery)
This energy is called an "electromagnetic wave" usually in the infrared range, this means that the energy that comes from the control remote has less energy than the visible red light (and this is why we can not see the light that comes out of the control remote), and this "signal" is read by the TV, in order to change of channel or change the volume.
You even can see that there is a sort of light (electromagnetic wave) coming out from it if you point with a camera to the small bulb that is in the front of the control remote.
Because the molecules are vibrating. Also keep in mind that when a substance is a solid its molecules are tightly packed. When it is a liquid its molecules are less compact