Answer:
the decay of half of the nuclei only a half-life has passed
, b) in rock time it is 1 108 years
Explanation:
The radioactive decay is given by
N = N₀ 
If half of the atoms have decayed
½ N₀ = N₀
½ =
₀
Ln 0.5 = - λ t
t = - ln 0.5 /λ
The definition of average life time is
= ln 2 / λ
λ = ln 2 /
λ = 0.693 / 100 10⁶
λ = 0.693 10⁻⁸ years
We replace
t = -ln 0.5 / 0.693 10⁻⁸
t = 10⁸ years
We see that for the decay of half of the nuclei only a half-life has passed
b) in rock time it is 1 108 years
Answer:
Explanation:
We define the linear density of charge as:
Where L is the rod's length, in this case the semicircle's length L = πr
The potential created at the center by an differential element of charge is:
where k is the coulomb's constant
r is the distance from dq to center of the circle
Thus.
Potential at the center of the semicircle
The block of wood is 3cm on each side so it is a cube. The volume of a cube is given by s^3. So the volume of this block is 3cm x 3cm x3 cm = 27 cm^3. density = mass/volume =27 g / 27 cm^3 = 1 g/cm^3
Answer:
thank for making me give up on life
Explanation:
I thought the stuff I had was hard wth is even that
Answer:
The increase in temperature of the bullet is 351.1 kelvin
Explanation:
First, we should find the kinetic energy of the bullet is:
with m the mass and v the velocity.
Now we know that half of the kinetic energy of the bullet is transformed into internal energy, by second's law of thermodynamics that means heat (Q) to raise bullet temperature (T), so:
To know what the increase in temperature is, we should use specific heat of lead:
The equation that relates specific heat, change in temperature and mass is:
solving for 
:
