Yes you do nees air to hear sound
Answer:
t = 37 x 10⁻⁶ m
Explanation:
given,
Length of glass plate,L = 9.47 cm
wavelength of the light, λ = 585 nm
Number of bands, n = 127 bands
thickness of the hair, t = ?
When the light get refracted from the inner surface of glass the wavelength of the light does not changes.
But when the light is refracted from the outer surface there is a dark band which shows that the wavelength changes.
now,
For the first order of bright band has phase difference = λ/2
for nth order
p = 2 t
t = 37 x 10⁻⁶ m
Hence the thickness of the hair is equal to t = 37 x 10⁻⁶ m
Electrons are negatively charged particles whereas protons are positively charged particles.
When a negative is shown on the bar, this means that the difference between the electrons and protons is a negative value, which also means that the number of electrons (negative particles) is more than the number of protons (positive particles).
Based on the above, the correct choice would be:
<span>D. There are more electrons than protons
</span>
Answer:
1.429*10^-5 m
Explanation:
From the question, we are given that
Diameter of the cable, d = 3 cm = 0.03 m
Force on the cable, F = 2 kN
Young Modulus, Y = 2*10^11 Pa
Area of the cable = πd²/4 = (3.142 * 0.03²) / 4 = 0.0028 / 4 = 0.0007 m²
The fractional length = Δl/l
Δl/l = F/AY
Δl/l = 2000 / 0.0007 * 2*10^11
Δl/l = 2000 / 1.4*10^8
Δl/l = 1.429*10^-5 m
Therefore, the fractional length is 1.429*10^-5 m long
Answer:
magnification will be -0.025
Explanation:
We have given the radius of curvature = 12 cm
And object distance = 3 m
So focal length
Now for mirror we know that
So
v = 0.750 m
Now magnification of the mirror is