An alternating voltage is described by 𝑣 = 50 𝑐𝑜𝑠 𝑡 (𝑣𝑜𝑙𝑡𝑠).

Question

The value of the stress at 𝑡=𝜋/4 (seconds) is:

A) 25 √2 V.

(B) 30 V.

(C) 30 √2 V.

(D) 30 √3 V.

(E) 50 V.

Answer 1

The voltage (v) at t=π/4

v=50 Cos(t) V=50 Cos (π/4) V=50*√2/2 V=25√2 V

v=25√2 V

Answer: The answer is A, v=25√2 V