Question

The voltage across a 7 H inductor is 22 (3.8 - e ^3t) V. If the initial current through the inductor is 1.4 A, find the current and the energy stored in the inductor at t= 2.5 s.​

Answer 1

Explanation:

C)

Let the cost price be x

Since profit is given as 20%, selling price will be (1+0.2)x

Thus, selling price would be 1.2x.

When C.P. and S.P. are Rs. 20 less then,

C.P. =x−20

S.P. =1.2x−20

According to the given condition,

Now, 1.2x−20=1.3×(x−20)

⇒1.2x−20=1.3x−26

⇒1.3x−1.2x=−20+26

⇒0.1x=6

⇒x=60

therefore, the cost price of the article is Rs. 60.