Answer:
the free electron density of lithium is 2.3 × 10²⁸ /m³
Explanation:
The Fermi energy is 4.72 eV.
The Fermi energy (highest filled orbital energy ) of free electron is

Rearrange the above equation for free electron density of lithium

where,
h = 6.626 × 10⁻³⁴J.s
= 9.11 × 10⁻³¹kg
= 4.72eV

Thus, the free electron density of lithium is 2.3 × 10²⁸ /m³
Answer:
Δx is the path difference between the two waves.
...
Phase Difference And Path Difference Equation.
Formula Unit
Phase Difference \Delta \phi=\frac{2\pi\Delta x}{\lambda } Radian or degree
Path Difference \Delta x=\frac{\lambda }{2\pi }\Delta \phi meter
Answer:
this is impossible for me
Explanation:
Answer:
25.08m/s
Explanation:
mgh1 + 0.5mv1² = mgh2 + 0.5mv2²
h1 = 0m
v1 = u
h2 = 5m
v2 = 23m/s
putting the values into the formula above;
m(10)(0) + 0.5m(u²) = m(10)(5) + 0.5m(23²)
0 + 0.5mu² = 50m + 264.5m
0.5mu² = 314.5m
dividing through by m
0.5u² = 314.5
u² = 629
u = <u>2</u><u>5</u><u>.</u><u>0</u><u>8</u><u>m</u><u>/</u><u>s</u>
<u>Theref</u><u>ore</u><u>,</u><u> </u><u>the</u><u> </u><u>init</u><u>ial</u><u> </u><u>speed</u><u> </u><u>"</u><u>u</u><u>"</u><u> </u><u>=</u><u> </u><u>2</u><u>5</u><u>m</u><u>/</u><u>s</u>
Answer:
17 °C
Explanation:
From specific Heat capacity.
Q = cm(t₂-t₁)................. Equation 1
Where Q = Heat absorb by the metal block, c = specific heat capacity of the metal block, m = mass of the metal block, t₂ = final temperature, t₁ = Initial temperature.
make t₁ the subject of the equation
t₁ = t₂-(Q/cm)............... Equation 2
Given: t₂ = 22 °C, Q = 5000 J, m = 4 kg, c = 250 J/kg.°c
Substitute into equation 2
t₁ = 22-[5000/(4×250)
t₁ = 22-(5000/1000)
t₁ = 22-5
t₁ = 17 °C