Answer:
a) 4.9*10^-6
b) 5.71*10^-15
Explanation:
Given
current, I = 3.8*10^-10A
Diameter, D = 2.5mm
n = 8.49*10^28
The equation for current density and speed drift is
J = I/A = (ne) Vd
A = πD²/4
A = π*0.0025²/4
A = π*6.25*10^-6/4
A = 4.9*10^-6
Now,
J = I/A
J = 3.8*10^-10/4.9*10^-6
J = 7.76*10^-5
Electron drift speed is
J = (ne) Vd
Vd = J/(ne)
Vd = 7.76*10^-5/(8.49*10^28)*(1.60*10^-19)
Vd = 7.76*10^-5/1.3584*10^10
Vd = 5.71*10^-15
Therefore, the current density and speed drift are 4.9*10^-6
And 5.71*10^-15 respectively
Answer:
Following are the solution to this question:
Explanation:
Law:




Because you know that gravity is in m/s^2 so, period will be measured in seconds. You know the cable is 12m long and gravity is 9.81 solve for T (period) 2π12sqrt(9.81)=6.94922
Answer:
a) Beth will reach before Alan
b)Beth has to wait 20 min for Alan to arrive
Explanation:
let 'd' be distance b/w Los Angeles and San Francisco i.e 400 mi
considering ,
Alan's speed
=50mph
Beth's speed
=60mph
->For Alan:
The time required
= d/
= 400/50 => 8h
-> For beth:
The time required
=> 6h 40m
Alan will reach at 8:00 a.m +8h = 4:00p.m.
Beth will reach at 9:00 a.m +6h 40m= 3:40p.m.
a) Beth will reach before Alan
b)Beth has to wait 20 min for Alan to arrive
Answer:
(A) 2.4 N-m
(B) 
(C) 315.426 rad/sec
(D) 1741.13 J
(E) 725.481 rad
Explanation:
We have given mass of the disk m = 4.9 kg
Radius r = 0.12 m, that is distance = 0.12 m
Force F = 20 N
(a) Torque is equal to product of force and distance
So torque
, here F is force and r is distance
So 
(B) Moment of inertia is equal to 
So 
Torque is equal to 
So angular acceleration 
(C) As the disk starts from rest
So initial angular speed 
Time t = 4.6 sec
From first equation of motion we know that 
So 
(D) Kinetic energy is equal to 
(E) From second equation of motion
