Answer:
2.54 μA
Explanation:
The current I in the wire is I = ∫∫J(r)rdrdθ
Since J(r) = Br, in the radial width of 13.1 μm, dr = 13.1 μm. r = 1.50 mm. We have a differential current dI. We remove the first integral by integrating dθ from θ = 0 to θ = 2π.
So, dI = J(r)rdrdθ ⇒ dI/dr = ∫J(r)rdθ = ∫Br²dθ = Br²∫dθ = 2πBr²
Now I = (dI/dr)dr evaluate at r = 1.50 mm = 1.50 × 10⁻³ m and dr = 13.1 μm = 0.013 mm = 0.013 × 10⁻³ m
I = (2πBr²)dr = 2π × 2.34 × 10 A/m³ × (1.50 × 10⁻³ m)² × 0.013 × 10⁻³ m = 2544.69 × 10⁻⁹ A = 2.54 × 10⁻⁶ A = 2.54 μA
17.86m/s
Explanation:
Given parameters:
Displacement of the ball = 50m
Time taken = 2.8s
Unknown:
Velocity of the ball = ?
Solution:
velocity is the rate of change of displacement with time
Velocity =
Velocity = = 17.86m/s
Learn more:
velocity brainly.com/question/5248528
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Boy X and Boy Y both move backward in opposite directions.
Answer:
We first to know that if the wheel rotates from rest means that at t=0 the velocity and the angle rotated is 0.
Then, we know:
Integrating 2 times, we have:
For the first 27.9 s, we have:
w = 37.107 rad/s
angle = 517.6426 rad
For the next seconds, according to the text, the angular velocity is constant so
w = 37.107 rad/s and hence, integrating:
Then, the time remaining is:
53.5 - 27.9 = 25.6
So for the next 25.6 seconds we have:
Finally, we add the 2 angles and we have as a result: