Answer:
A. Zero
Explanation:
The force on a coil of N turns, enclosing an area, A and carrying a current I in the presence of a magnetic field B, is :
F = N * I * A * B * sinθ
Where θ is the angle between the normal of the enclosed area and the magnetic field.
Since the normal of the area is parallel to the magnetic field, θ = 0
Hence:
F = NIABsin0
F = 0 or Zero
Quantity of Charge , Q = ne
Where n = number of electrons
e = charge on one electron = -1.6 * 10 ^-19 C.
n = 50 * 10^31 electrons
Q = (50 * 10^31)*( -1.6 * 10 ^-19 ) = -8 * 10^13 C.
Note that the minus sign indicates that the charge is a negative charge.
Answer:

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%
Explanation:
From the exercise we know two information. The real speed and the experimental measured by the speedometer

Since the speedometer is only accurate to within 0.1km/h the experimental speed is

Knowing that we can calculate Kinetic energy for the real and experimental speed


Now, the potential error in her calculated kinetic energy is:

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Answer:
The pressure and maximum height are
and 161.22 m respectively.
Explanation:
Given that,
Diameter = 3.00 cm
Exit diameter = 9.00 cm
Flow = 40.0 L/s²
We need to calculate the pressure
Using Bernoulli effect

When two point are at same height so ,
....(I)
Firstly we need to calculate the velocity
Using continuity equation
For input velocity,




For output velocity,


Put the value into the formula



(b). We need to calculate the maximum height
Using formula of height

Put the value into the formula



Hence, The pressure and maximum height are
and 161.22 m respectively.