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
Answer:
7.344 s
Explanation:
A = 0.15 x 0.3 m^2 = 0.045 m^2
N = 240
e = - 2.5 v
B1 = 0.1 T
B2 = 1.8 T
ΔB = B2 - B1 = 1.8 - 0.1 = 1.7 T
Δt = ?
e = - dФ/dt
e = - N x A x ΔB/Δt
- 2.5 = - 240 x 0.045 x 1.7 / Δt
2.5 = 18.36 / Δt
Δt = 7.344 s
They can't hear an echo in small room because in it the sound can't be reflected back. For an echo of a sound to be heard,the minimum distance between the source of sound and the walls of the roomshould be 17.2 m. Obviously,in asmall room echoes cannot beheard.
