1.) In some places, insect \"zappers\", with their blue lights, are a familiar s

Question

1.) In some places, insect "zappers", with their blue lights, are a familiar sight on a summer's night. These devices use a high voltage to electrocute insects. One such device uses an ac voltage of 4375 V, which is obtained from a standard 120-V outlet by means of a transformer. If the primary coil has 21 turns, how many turns are in the secondary coil?

2.)The resistances of the primary and secondary coils of a transformer are 57.6 and 16.2 , respectively. Both coils are made from lengths of the same copper wire. The circular turns of each coil have the same diameter. Find the turns ratio Ns/Np.

Explanation / Answer

1)Given,

Vpri = 120 V ; Npri = 21

Vsec = 4375 V ; Nsec = ?

We know that

Npri/Nsec = Vpri/Vsec

Nsec = (Vsec/Vpri)Npri

Nsec = (4375/120)21 = 765.63 turns

Hence, Nsec = 765.63 = 766 turns

2)Rp = 57.6 ; Rs = 16.2

Ns/Np = Vs/Vp = Rs/Rp = 16.2/57.6 = 0.2813

Hence, Ns/Np = 0.2813

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.