When the light bulb is powered from an element with an EMF of 1.5 V, the current in the circuit is 0.2 A.

When the light bulb is powered from an element with an EMF of 1.5 V, the current in the circuit is 0.2 A. Find the work of external forces in the element in 1 min?

Data: ε (EMF of the element that powers the light bulb) = 1.5 V; I (current) = 0.2 A; t (duration of the element) = 1 min (in SI t = 60 s).

To find the work of external forces in the element used, we apply the formula: ε = Ast / q, whence Ast = ε * q = ε * I * t.

Let’s calculate: Ast = 1.5 * 0.2 * 60 = 18 J.

Answer: 4. The work of external forces in the element used is 18 J.