Answer:
B = 9.16 10⁻² T
Explanation:
The speed selector is a configuration where the electric and magnetic force has the opposite direction, which for a specific speed cancel
q v B = q E
v = E / B
B = E / v
Let's calculate
B = 4.4 10⁵ / 4.8 10⁶
B = 9.16 10⁻² T
Answer:
Explanation:
The work required to push will be equal to work done by friction . Let d be the displacement required .
force of friction = mg x μ where m is mass of the suitcase , μ be the coefficient of friction
work done by force of friction
mg x μ x d = 660
80 x 9.8 x .272 x d = 660
d = 3 .1 m .
a. The disk starts at rest, so its angular displacement at time
is
![\theta=\dfrac\alpha2t^2](https://tex.z-dn.net/?f=%5Ctheta%3D%5Cdfrac%5Calpha2t%5E2)
It rotates 44.5 rad in this time, so we have
![44.5\,\mathrm{rad}=\dfrac\alpha2(6.00\,\mathrm s)^2\implies\alpha=2.47\dfrac{\rm rad}{\mathrm s^2}](https://tex.z-dn.net/?f=44.5%5C%2C%5Cmathrm%7Brad%7D%3D%5Cdfrac%5Calpha2%286.00%5C%2C%5Cmathrm%20s%29%5E2%5Cimplies%5Calpha%3D2.47%5Cdfrac%7B%5Crm%20rad%7D%7B%5Cmathrm%20s%5E2%7D)
b. Since acceleration is constant, the average angular velocity is
![\omega_{\rm avg}=\dfrac{\omega_f+\omega_i}2=\dfrac{\omega_f}2](https://tex.z-dn.net/?f=%5Comega_%7B%5Crm%20avg%7D%3D%5Cdfrac%7B%5Comega_f%2B%5Comega_i%7D2%3D%5Cdfrac%7B%5Comega_f%7D2)
where
is the angular velocity achieved after 6.00 s. The velocity of the disk at time
is
![\omega=\alpha t](https://tex.z-dn.net/?f=%5Comega%3D%5Calpha%20t)
so we have
![\omega_f=\left(2.47\dfrac{\rm rad}{\mathrm s^2}\right)(6.00\,\mathrm s)=14.8\dfrac{\rm rad}{\rm s}](https://tex.z-dn.net/?f=%5Comega_f%3D%5Cleft%282.47%5Cdfrac%7B%5Crm%20rad%7D%7B%5Cmathrm%20s%5E2%7D%5Cright%29%286.00%5C%2C%5Cmathrm%20s%29%3D14.8%5Cdfrac%7B%5Crm%20rad%7D%7B%5Crm%20s%7D)
making the average velocity
![\omega_{\rm avg}=\dfrac{14.8\frac{\rm rad}{\rm s}}2=7.42\dfrac{\rm rad}{\rm s}](https://tex.z-dn.net/?f=%5Comega_%7B%5Crm%20avg%7D%3D%5Cdfrac%7B14.8%5Cfrac%7B%5Crm%20rad%7D%7B%5Crm%20s%7D%7D2%3D7.42%5Cdfrac%7B%5Crm%20rad%7D%7B%5Crm%20s%7D)
Another way to find the average velocity is to compute it directly via
![\omega_{\rm avg}=\dfrac{\Delta\theta}{\Delta t}=\dfrac{44.5\,\rm rad}{6.00\,\rm s}=7.42\dfrac{\rm rad}{\rm s}](https://tex.z-dn.net/?f=%5Comega_%7B%5Crm%20avg%7D%3D%5Cdfrac%7B%5CDelta%5Ctheta%7D%7B%5CDelta%20t%7D%3D%5Cdfrac%7B44.5%5C%2C%5Crm%20rad%7D%7B6.00%5C%2C%5Crm%20s%7D%3D7.42%5Cdfrac%7B%5Crm%20rad%7D%7B%5Crm%20s%7D)
c. We already found this using the first method in part (b),
![\omega=14.8\dfrac{\rm rad}{\rm s}](https://tex.z-dn.net/?f=%5Comega%3D14.8%5Cdfrac%7B%5Crm%20rad%7D%7B%5Crm%20s%7D)
d. We already know
![\theta=\dfrac\alpha2t^2](https://tex.z-dn.net/?f=%5Ctheta%3D%5Cdfrac%5Calpha2t%5E2)
so this is just a matter of plugging in
. We get
![\theta=179\,\mathrm{rad}](https://tex.z-dn.net/?f=%5Ctheta%3D179%5C%2C%5Cmathrm%7Brad%7D)
Or to make things slightly more interesting, we could have taken the end of the first 6.00 s interval to be the start of the next 6.00 s interval, so that
![\theta=44.5\,\mathrm{rad}+\left(14.8\dfrac{\rm rad}{\rm s}\right)t+\dfrac\alpha2t^2](https://tex.z-dn.net/?f=%5Ctheta%3D44.5%5C%2C%5Cmathrm%7Brad%7D%2B%5Cleft%2814.8%5Cdfrac%7B%5Crm%20rad%7D%7B%5Crm%20s%7D%5Cright%29t%2B%5Cdfrac%5Calpha2t%5E2)
Then for
we would get the same
.
Answer:
Explanation:
Parameters given:
Mass of Puck 1, m = 1 kg
Mass of Puck 2, M = 1 kg
Initial velocity of Puck 1, u = 20 m/s
Initial velocity of Puck 2, U = 0 m/s
Final velocity of Puck 1, v = 5 m/s
Since we are told that momentum is conserved, we apply the principle of conservation of momentum:
Total initial momentum of the system = Total final momentum of the system
mu + MU = mv + MV
(1 * 20) + (1 * 0) = (1 * 5) + (1 * V)
20 = 5 + V
V = 20 - 5 = 15 m/s
Puck 2 moves with a velocity of 15 m/s
Answer:
The total electrical power we are using is: 1316 W.
Explanation:
Using the ohm´s law
and the formula for calculate the electrical power, we can find the total electrical power that we are using. First we need to find each electrical power that is using every single component, so the radio power is:
, so the radio power is:
, then we find the pop-corn machine power as:
and finally there are three light bulbs of 110(W) so: P=3*110(W)=330(W) and the total electrical power is the adding up every single power so that: P=330(W)+770(W)+216(W)=1316(W).