Answer:
) the uniform disk has a lower moment of inertia and arrives first.
Explanation:
(a) the uniform disk has a lower moment of inertia and arrives first.
(b) Let's say the disk has mass m and radius r, and
the hoop has mass M and radius R.
disk: initial E = PE = mgh
I = ½mr², so KE = ½mv² + ½Iω² = ½mv² + ½(½mr²)(v/r)² = (3/4)mv² = mgh
m cancels, leaving v² = 4gh / 3
hoop: initial E = Mgh
I = MR², so KE = ½MV² + ½(MR²)(V/R)² = MV² = Mgh
M cancels, leaving V² = gh
Vdisk = √(4gh/3) > Vhoop = √(gh)
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[D. 2 protons, 2 electrons, and 1 neutron.]
As we know that, protons are embedded in the nucleus with neutron having no charge. So, nucleus has positive charge. Electrons are revolved around the nucleus of the atom. Proton has positive charge and electron has negative charge.
Number of proton = Number of electron.
Hence, both 2 protons and 2 electrons make the atom electrically neutral. So, the net charge of atom is 0. Neutron are the subatomic particle which has only mass.
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Answer:
the third one is incorrect
Explanation:
10 x 10³= 10^1 x 10^3 = 10^4
In optics, you have to create a layer of coating that is approximately 1/4 of the light's wavelength. The working equation for this problem is:
d = λ₀/4n,
where
λ₀ is the wavelength of the incident light
n is the refractive index of the coating
Substituting the values,
d = (650 nm)/4(1.39)
<em>d = 116.9 nm</em>
Answer:
e, Relay
Explanation:
When short circuit or serious overload current occurs in the circuit,,the electromagnet generates enough suction to cut off the power supply.
