Answer:
a) E_{L} = -360 V
, b) t = 3 s
Explanation:
The electromotive force in an inductor is
= - L dI/ dt
in the exercise they give us the relation of i (t)
i (t) = 1.00 t² -6.00t
we carry out the derivative and substitute
E_{L} = - L (2.00 2t - 6.00 1)
a) the electromotive force at t = 1.00 s
E_{L} = - 90.0 (4.00 1 - 6.00)
E_{L} = -360 V
b) for t = 4 s
E_{L}= - 90 (2 4 2 - 6 4)
E_{L} = - 720 V
c) for the induced electromotive force to zero, the amount between paracentesis must be zero
(2.00 t2 - 6.00t) = 0
t (2.0 t-6.00) = 0
the solutions of this equation are
t = 0
2 t -6 = 0
t = 3 s
to have a different solution the trivial (all zero) we must total t = 3 s
Answer: a) The acceletarion is directed to the center on the turntable. b) 5 cm; ac= 0.59 m/s^2; 10 cm, ac=1.20 m/s^2; 14 cm, ac=1.66 m/s^2
Explanation: In order to explain this problem we have to consider teh expression of the centripetal accelartion for a circular movement, which is given by:
ac=ω^2*r where ω and r are the angular speed and teh radios of the circular movement.
w=2*π*f
We know that the turntable is set to 33 1/3 rev/m so
the frequency 33.33/60=0.55 Hz
then w=2*π*0.55=3.45 rad/s
Finally the centripetal acceleration at differents radii results equal:
r= 0.05 m ac=3.45^2*0.05=0.50 m/s^2
r=0.1 ac=3.45^2*0.1=1.20 m/s^2
r=0.14 ac=3.45^2*0.14=1.66 m/s^2
Answer:
The SI unit of pressure is Pascal .
Answer:
The ampere was chosen as a base unit, because it is easily measured whereas the coloumb is not. Interestingly, there is a move a foot to redefine the ampere (which will remain a base unit) in terms of the fundamental charge on an electron (not in terms of coulomb).
Explanation: