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1 year ago

A boy threw a ball upward and it took 3 sec to reach the highest point. Determine the initial velocity of the ball.

Physics

1 answer:

makkiz [27]1 year ago

6 0

Answer:

V initial = 29.4 m.s²

Explanation:

( Using the laws of motion)

V final = V initial + Acceleration × time

0 = V initial + ( -9.8)(3)

29.4 = V initial

* I took upward as positive that's why I substituted -9.8 *

* for V final we know that at maximum height the ball is not moving thats why is = 0 *

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Answer:

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b. u = 17230.6 J/m³

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a. In order to calculate the magnetic field in the solenoid you use the following formula:

$B=\frac{\mu_o n i}{L}$ (1)

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$u=\frac{B^2}{2\mu_o}=\frac{(0.20T)^2}{2(4\pi*10^{-7}T/A)}=17230.6\frac{J}{m^3}$

The energy density is 17230.6 J/m³

c. The total energy contained in the solenoid is:

$E=uV$ (2)

V is the volume of the solenoid and is calculated by assuming the solenoid as a perfect cylinder:

$V=AL$

A: cross-sectional area of the solenoid = 0.550 cm^2 = 5.5*10^-5m^2

$V=(5.5*10^{-5}m^2)(0.25m)=1.375*10^{-5}m^3$

Then, the energy contained in the solenoid is:

$E=(17230.6J/m^3)(1.375*10^{-5}m^3)=0.236J$

The energy contained is 0.236J

d. The inductance of the solenoid is calculated as follow:

$L=\frac{\mu_o N^2 A}{L}=\frac{(4\pi*10^{-7}T/A)(460)^2(5.5*10^{-5}m^2)}{0.25m}\\\\L=5.84*10^{-5}H$

The inductance of the solenoid is 5.84*10^-5 H

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