mass times specific heat times tem change.
57 x sh x (30-11)
convert to mks and look up sh iron
Answer:
f = 7.9487 10¹³ Hz
Explanation:
The photoelectric effect was correctly explained by Einstein assuming that the radiation is composed of photons, which behave like particles.
hf = K + Ф
It indicates the frequency and the kinetic energy, let's look for the work function
Ф = hf - K
let's reduce the magnitudes to the SI system
K = 0.332 eV (1.6 10⁻¹⁹ J / 1 eV) = 0.5312 10⁻⁻¹⁹ J
let's calculate
Ф = 6.63 10⁻⁻³⁴ 6.64 10¹¹ - 0.5312 10⁻¹⁹
Ф = 4.40 10⁻²² - 0.5312 10⁻¹⁹
Ф = 5.27 10⁻²⁰ J
for the minimum frequency that produces photoelectrons, the kinetic energy is zero
hf = Ф
f = Ф / h
f = 5.27 10⁻²⁰ / 6.63 10⁻³⁴
f = 7.9487 10¹³ Hz
Fast Communication, can be used for good and can be used for bad hackers.
Answer:
the correct answer is c, they will accelerate away from each other at different speeds. the 80kg will go faster due to less mass
Answer:
The new height the ball will reach = (1/4) of the initial height it reached.
Explanation:
The energy stored in any spring material is given as (1/2)kx²
This energy is converted to potential energy, mgH, of the ball at its maximum height.
If the initial height reached is H
And the initial compression of the spring = x
So, mgH = (1/2)kx²
H = kx²/2mg
The new compression, x₁ = x/2
New energy of loaded spring = (1/2)kx₁²
And the new potential energy = mgH₁
mgH₁ = (1/2)kx₁²
But x₁ = x/2
mgH₁ = (1/2)k(x/2)² = kx²/8
H₁ = kx²/8mg = H/4 (provided all the other parameters stay constant)