Answer:
<em>His angular velocity will increase.</em>
Explanation:
According to the conservation of rotational momentum, the initial angular momentum of a system must be equal to the final angular momentum of the system.
The angular momentum of a system =
'ω'
where
' is the initial rotational inertia
ω' is the initial angular velocity
the rotational inertia = 
where m is the mass of the system
and r' is the initial radius of rotation
Note that the professor does not change his position about the axis of rotation, so we are working relative to the dumbbells.
we can see that with the mass of the dumbbells remaining constant, if we reduce the radius of rotation of the dumbbells to r, the rotational inertia will reduce to
.
From
'ω' =
ω
since
is now reduced, ω will be greater than ω'
therefore, the angular velocity increases.
C and d have the same amount of protons and electrons
Answer:
Night vision is the ability to see in low-light conditions. Whether by biological or technological means, night vision is made possible by a combination of two approaches: sufficient spectral range, and sufficient intensity range.
Answer: D
Wavelength λ = 7.5 × 10^-11 m
Explanation:
You are given the frequency of an electromagnetic wave to be:
F = 4.0 x 1018 Hz. And the speed of light C to be
C = 3 × 10^8 m/s
From wave speed formula:
Wave speed is the product of waves frequency and wavelength. That is,
V = fλ
Where
f = frequency
λ = wavelength
V = C = speed of light
Substitute the values of the parameters into the formula
C = fλ
3 × 10^8 = 4 × 10^18 × λ
Make λ the subject of formula
λ = (3×10^8)/(4×10^18)
λ = 7.5 × 10^-11 m
Therefore, the wavelength of the wave is 7.5 × 10^-11 m