Power = (voltage) x (current)
Power = (240 volts) x (4 Amp)
Power = 960 watts
The momentum of both the identical balls would eventually be transferred to one another when it comes to a point wherein they will collide. In addition, the phenomenon is called an elastic collision wherein both the momentum and energy of the system would considered to be conserved.
For this case we first think that the skateboard and the child are one body.
We have then:
1 = jug
2 = skateboard + boy
By conservation of the linear amount of movement:
M1V1i + M2V2i = M1V1f + M2V2f
Initial rest:
v1i = v2i = 0
0 = M1V1f + M2V2f
Substituting values
0 = (7.8) (3.2) + (M2) (- 0.65)
0 = 24.96 + M2 (-0.65)
-24.96 = (-0.65) M2
M2 = (-24.96) / (- 0.65) = 38.4 kg
Then, the child's mass is:
M2 = Mskateboard + Mb
Clearing:
Mb = M2-Mskateboard
Mb = 38.4 - 1.9
Mb = 36.5 Kg
answer:
the boy's mass is 36.5 Kg
Inductive reactance (Z) = ω L = 2Πf L = (2Π) (12,000) (L)
I = V / Z
4 A = 16v / (24,000Π L)
Multiply each side by (24,000 Π L):
96,000 Π L = 16v
Divide each side by (96,000 Π) :
L = 16 / 96,000Π = 5.305 x 10⁻⁵ Henry
L = 53.05 microHenry