Answer:
B = 0.37T
Explanation:
In order to calculate the needed magnitude of the magnetic force you use the following formula, which calculate the induced emf of the solenoid when there is a change in the magnetic flux:
(1)
emf: induced voltage in the solenoid = 10,000V
N: turns of the solenoid = 525
ФB: magnetic flux
B: magnitude of the magnetic field = ?
A: cross-sectional area of the solenoid = π*r^2
r: radius of the cross-sectional area = 0.260m
Δt: interval time of the change of the magnetic flux = 4.17ms = 4.17*10^-3s
First, you have the magnetic field direction perpendicular to the plane of the solenoid, after, the angle between them is 90° (quarter of a revolution)
In the equation (1) the only parameter that changes on time is the angle, then, you can solve for B from the equation (1):

Finally, you replace the values of the parameters to calculate B:

The strength of the magnetic field is 0.37T
Answer:
Explanation:
At the lowest point velocity is zero
loss of potential energy = gain of spring energy
= mgh = 1/2 k h² , h is vertical downward displacement , k is spring constant
2 mg = k h
h = 2mg / k
= (2 x .2 x 9.8) / 50
= .0784 m
P E ( gravitational) = - mgh
= - .2 x 9.8 x .0784
= - .1536 J
spring PE = + .1536 J
Total PE = 0
b )
At mid point ie at h = .0392 m
gravitational PE = .2 X 9.8 X .0392
= - .0768 J
Elastic PE = 1/2 X 50 X .0392² = .0384 J
Total = - .0768 J + .0384 J
= - .0384 J
At mid point total energy = 0
- .0384 + KE = 0
KE = .0384 J
c )
1/2 m v ² = .0384
v² = 2 x .0384 / .2
= .384
v = .6196 m / s
62 cm / s
Answer: 116.926 km/h
Explanation:
To solve this we need to analise the relation between the car and the Raindrops. The cars moves on the horizontal plane with a constant velocity.
Car's Velocity (Vc) = 38 km/h
The rain is falling perpedincular to the horizontal on the Y-axis. We dont know the velocity.
However, the rain's traces on the side windows makes an angle of 72.0° degrees. ∅ = 72°
There is a relation between this angle and the two velocities. If the car was on rest, we will see that the angle is equal to 90° because the rain is falling perpendicular. In the other end, a static object next to a moving car shows a horizontal trace, so we can use a trigonometric relation on this case.
The following equation can be use to relate the angle and the two vectors.
Tangent (∅) = Opposite (o) / adjacent (a)
Where the Opposite will be the Rain's Vector that define its velocity and the adjacent will be the Car's Velocity Vector.
Tan(72°) = Rain's Velocity / Car's Velocity
We can searching for the Rain's Velocity
Tan(72°) * Vc = Rain's Velocity
Rain's Velocity = 116.926 km/h