Question

The magnetic flux through a coil perpendicular to its plane is varying according to the relation Φ = (5t³ + 4t² + 2t - 5) Weber. If the resistant of the coil is 5 ohm, then the induced current through the coil at t = 2 sec will be ______.

Options

• 15.6 A

• 16.6 A

• 17.6 A

• 18.6 A

Answer 1

The magnetic flux through a coil perpendicular to its plane is varying according to the relation Φ = (5t³ + 4t² + 2t - 5) Weber. If the resistant of the coil is 5 ohm, then the induced current through the coil at t = 2 sec will be 15.6 A.

Explanation:

Φ = (5t³ + 4t² + 2t - 5)

|e| = 15t² + 8t + 2     `[∵ |"e"| = ("d"phi)/"dt" ]`

R = 5Ω

So, i = `|"e"|/"R"=(15"t"^2+8"t"+2)/5`

= 3t² + 1.6t + 0.4

= 3.2² + 1.6 × 2 + 0.4 

= 15.6 A  (∵ t = 2 sec)