Please explain the questions below: 1. Two long parallel wires each carry a curr
ID: 1499906 • Letter: P
Question
Please explain the questions below:
1. Two long parallel wires each carry a current of 5.0 A directed to the east. The two wires are separated by 8.0 cm. What is the force per unit length in one of the wires?
2. A body oscillates with simple harmonic motion along the x-aixs. Its displacement varies with time according to the equation x= 5 sin ( pi*t + pi/ 3). The period of the motion is?
3. A body of mass 4.6 kg is suspended from a vertical spring and oscillates with simple harmonic motion. Its displacement varies with time according to the equation
y= 5 sin ( 8.4 t + pi/ 3) . By how much does the spring stretch when that 4.6 kg mass is initially attached to the spring?
Explanation / Answer
(1)
Force per unit length in one of the wires is given by,
F/L = (uo*I1*I2)/(2**r)
F/L = (2*10^-7 * 5.0^2)/(8.0*10^-2)
F/L = 6.25 * 10^-5 N/m
(2)
x(t) = A sin( t + )
x= 5 sin ( pi*t + pi/ 3)
Comparing the two eq, =
(2*)/t =
t = 2.0 s
Period of the motion, t = 2.0 s
(3)
y= 5 sin ( 8.4 t + pi/ 3)
x(t) = A sin( t + )
= sqrt(k/m)
8.4 = sqrt(k/4.6)
k = 324.5 N/m
Now, F = k*x
4.6 * 9.8 = 324.5 * x
x = 0.1389 m
Stretch in spring, x = 13.9 cm