Edwin Smith found an ancient Egyptian papyrus that discussed medical concerns
Before solving this question first we have to understand work function.
The work function of a metal is amount of minimum energy required to emit an electron from the surface barrier of metal . Whenever the metal will be exposed to radiation a part of its energy will be utilized to emit an electron while rest will provide kinetic energy to the electron.
Let f is the frequency of incident radiation and f' is the frequency corresponding to work function. Let v is the velocity of the ejected electron.
we know that velocity of an electromagnetic wave is the product of frequency and wavelength. Hence frequency f is given as-
where c is velocity of light and is the wavelength of the wave.
As per the question incident wavelength =313 nm
[as 1 nm =10^-9 m]
The wavelength corresponding to work function is 351 nm i.e
we know that hf=hf'+K.E [ h is the planck's constant whose value is 6.63×10^-34 J-s]
⇒K.E =hf-hf'
[ans]
Answer:
dP/dt = 26.12 W/s
Explanation:
First, we need to find the value of dt at the instant when R₃ becomes 91.7 Ω. Therefore, we use:
dR₃/dt = 0.552 Ω/s
where,
dR₃ = Change in value of resistance 3 = 91.7 Ω - 7.42 Ω = 84.28 Ω
dt = time interval = ?
Therefore,
84.28 Ω = (0.552 Ω/s)(dt)
dt = (84.28 Ω)/(0.552 Ω/s)
dt = 152.68 s
Now, we find change in power (dP):
dP = V(R₁ + R₂ + dR₃)
dP = (42.1 V)(2.96 Ω + 7.48 Ω + 84.28 Ω)
dP = 3987.71 W
Dividing by dt:
dP/dt = 3987.71 W/152.68 s
<u>dP/dt = 26.12 W/s</u>
When object density is lesser than liquid density, it floats....BUT when it's density is greater than the liquid density, then it sinks...
Answer:
The mass of the block, M =T/(3a +g) Kg
Explanation:
Given,
The upward acceleration of the block a = 3a
The constant force acting on the block, F₀ = Ma = 3Ma
The mass of the block, M = ?
In an Atwood's machine, the upward force of the block is given by the relation
Ma = T - Mg
M x 3a = T - Ma
3Ma + Mg = T
M = T/(3a +g) Kg
Where 'T' is the tension of the string.
Hence, the mass of the block in Atwood's machine is, M = T/(3a +g) Kg