4. When you walk across a rug ona dry day, your body can become electrified, and

Question

4.    When you walk across a rug ona dry day, your body can become electrified, and its electricpotential can change. When the potential becomes large enough, aspark of negative charges can jump between your hand and a metalsurface. A spark occurs when the electric field strength created bythe charges on your body reaches the dielectric strength of theair. The dielectric strength of the air is3.0×106 N/C and is the electricfield strength at which the air suffers electrical breakdown.Suppose a spark 3.0 mm long jumps between your hand and a metaldoorknob. Assuming that the electric field is uniform, find thepotential difference (Vknob –Vhand) between your hand and the doorknob.

Explanation / Answer

  Potentialdifference   V   =   Electricfield strength * distance    here   distance   d   =   3.0   mm   =   3.0 *10-3   m    Vknob   -   Vhand   =   3.0* 106 * 3.0 * 10-3                                  =   9.0* 103   V                                  =   9000.0   V                                  =   9.0* 103   V                                  =   9000.0   V

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

---

---

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