A single pulley has no advantage in reducing force. A single pulley only helps by changing direction of effort, pulling something from up to down feels easier then vice versa due to our muscles arrangement. However, the force needed is the same.
Meanwhile multiple pullies divide the tension. The lower pulley itself reduces the force into half so as to you feel a part of the tension while rest is suspended by the ceiling in the case in the diagram below.
Answer:
n = 1,875
Explanation:
The speed of light in vacuum is constant (c) and in a material medium it is
v = d / t
The refractive index of a material is defined by
n = c / v
Let's look for the speed of light in the material, in general the length that light travels is known, this value is high, x = 1, when we place a block on the road, a small amount is lengthened by the length of the block, which in general is despised
These measurements are made on a digital oscilloscope that allows to stop the signals and measure their differences, that is, the zero is taken when the first ray arrives and the time for the second ray is measured,
v = d / t
v = 1 / 6.25 10⁻⁹
v = 1.6 10⁸ m / s
we calculate the refractive index
n = 3 10⁸ / 1.6 10⁸
n = 1,875
Good afternoon!
We calculate the volume of the container in cm³. To do that, we must put the units in cm:
30 cm → 30 cm
50 mm → 5 cm
0.2 m → 20 cm
The volume is:
V = 30 . 5 . 20
V = 3000 cm³
Now, we calculate the mas with the formula:
m = dV
m = 2.5 · 3000
m = 7500 g
Dividing by 1000, we have the mass in kg:
m = 7.5 kg