Answer:
0 < r < r_exterior B_total =
r > r_exterior B_total = 0
Explanation:
The magnetic field created by the wire can be found using Ampere's law
∫ B. ds = μ₀ I
bold indicates vectors and the current is inside the selected path
outside the inner cable
B₁ (2π r) = μ₀ I
B₁ =
the direction of this field is found by placing the thumb in the direction of the current and the other fingers closed the direction of the magnetic field which is circular in this case.
For the outer shell
for the case r> r_exterior
B₂ = \frac{\mu_o I}{2\pi r}
This current is in the opposite direction to the current in wire 1, so the magnetic field has a rotation in the opposite direction
for the case r <r_exterior
in this case all the current is outside the point of interest, consequently not as there is no internal current, the field produced is zero
B₂ = 0
Now we can find the field created by each part
0 < r < r_exterior
B_total = B₁
B_total =
r > r_exterior
B_total = B₁ -B₂
B_total = 0
They send out waves differently and cannot be heard easily
Answer:
C. 21 Joules
Explanation:
We apply the formula to calculate the potential energy (Ep):
Ep=m*g*h
Where:
Ep : potential energy in Joules (J)
m :mass in kilograms (kg)
g acceleration due to gravity (m/s²)
h: height in meters (m)
Calculation of the height (h)
Ep = m*g*h
7 = (1.5 )*(9.8) *(h
)
7 = (14.7) (h
)
h = 7 / (14.7)
h= 0.476 m
Gravitational potential energy of the second object
Ep = m*g*h
Ep = (4.5 )*(9.8) *(0.476
)
Ep = (4.5 )*(9.8) *(0.476
)
Ep = 21 J
<h2>Answer: 10.52m</h2><h2 />
First, we have to establish the <u>reference system</u>. Let's assume that the building is on the negative y-axis and that the brick was thrown at the origin (see figure attached).
According to this, the initial velocity
has two components, because the brick was thrown at an angle
:
(1)
(2)
(3)
(4)
As this is a projectile motion, we have two principal equations related:
<h2>
In the x-axis:
</h2>
(5)
Where:
is the distance where the brick landed
is the time in seconds
If we already know
and
, we have to find the time (we will need it for the following equation):
(6)
(7)
<h2>
In the y-axis:
</h2>
(8)
Where:
is the height of the building (<u>in this case it has a negative sign because of the reference system we chose)</u>
is the acceleration due gravity
Substituting the known values, including the time we found on equation (7) in equation (8), we will find the height of the building:
(9)
(10)
Multiplying by -1 each side of the equation:
>>>>This is the height of the building