Answer:
K.E = 5.53 eV = 8.85 x 10⁻¹⁹ J
Explanation:
First we calculate the energy of photon:
E = hc/λ
where,
E = Energy of Photon = ?
h = Plank's Constant = 6.626 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = wavelength = 120 nm = 1.2 x 10⁻⁷ m
Therefore,
E = (6.626 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/(1.2 x 10⁻⁷ m)
E = (16.565 x 10⁻¹⁹ J)(1 eV/1.6 x 10⁻¹⁹ J)
E = 10.35 eV
Now, from Einstein's Photoelectric equation we know that:
Energy of Photon = Work Function + K.E of Electron
10.35 eV = 4.82 eV + K.E
K.E = 10.35 eV - 4.82 eV
<u>K.E = 5.53 eV = 8.85 x 10⁻¹⁹ J</u>
Answer:
The average kinetic energy of the molecules increases
Explanation:
The temperature of a substance is proportional to the average kinetic energy of the particles in the substance.
In fact, for an ideal gas for instance, there is the following relationship:
where
KE is the average kinetic energy of the particles
k is the Boltzmann's constant
T is the absolute temperature of the gas
When we heat a substance (such as the flask of water in this problem), we are giving thermal energy to the particles of the substance; therefore, these particles will move faster on average, so their kinetic energy will increase (and the temperature of the substance will increase as well).
Answer:
a) 100Hz
b) opened at both ends
c) 1.72m
Explanation:
Let fun be the nth Harmonic frequency organ. If pipe is opened at both ends.
L= length of pipe
Fyn =(n/x)
550hz= (n/2L)v 1
650hz=(n+1/2L)×v 2
Comparing 1 and 2
650hz= nv/2L + v/2L
550= 343/2L
L= 550×2/343 = 1.7m
c) fundamental frequency
Fo= nv/2L = 343/(2×1.7) = 100Hz
Answer:
250,000
Explanation:
<h2> </h2>
<h2>formula = ( F=ma </h2>
- F=1500N
- a=6m/s^2
- F= ma
- m=?
- 1500/6 = m
- m=250 kg
- 1kg =1000gm so 250kg =250,000gm
- m =250×10^3 gm
Those two units can be compared to a 'mile per hour' and a 'mile per hour - hour'.
One is a rate. The other is a quantity, after maintaining a rate for some time.
-- 'Joule' is a unit of energy. It's the amount of work (energy) you do
when you push with a force of 1 newton though a distance of 1 meter.
Lifting 10 pound of beans 3 feet off the floor takes about 40.7 joules of energy.
-- 'Watt' is a <u><em>rate</em></u> of using energy . . . 1 joule per second.
If you lift 10 pounds 3 feet off the floor in 1 second, your <em>power</em> is 40.7 watts.
-- 'Watt-second' is the amount of energy used in one second,
at the rate of 1 joule per second . . . 1 joule.
-- 'Watt-hour' is the amount of energy used in one hour,
at the rate of 1 joule per second . . . 3,600 joules.
-- 'Kilowatt' is a bigger <em>rate</em> of using energy . . . 1,000 joules per second.
-- 'Kilowatt - second' is the amount of energy used in one second,
at the rate of 1,000 joules per second . . . 1,000 joules .
-- 'Kilowatt - hour' is the amount of energy used in one hour,
at the rate of 1,000 joules per second . . . 3,600,000 joules .
Depending on where you live, 3,600,000 joules of energy bought
from the electric company costs something between 5¢ and 25¢.
