I hope this helps. it was right when i took the test.
Let
his and skateboard's combined mass is x
we know
F1=-F2
0.5kg*10m/s=-0.05m/s xkg
5=0.05x(minus cancel with the m/s as it represented the opposite direction of velocity and now there is no velocity in this equation.. so minus is avoidable. and the kgs cancel out)
x=10
so their combined mass is a 100 kg.. (I hope I didn't mess thing up for you)
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
