Precalculus 2014
74

Step-by-step Answer
 PAGE: 94 SET: Exercises PROBLEM: 74
Please look in your text book for this problem Statement

Voltage used by an electrical device is , where is the voltage in volts, is the power in watts, and is the resistance in ohms.

The function .

(a)

Find power consumption of the lamp.

Voltage.

Resistance.

Solve for .

Consider .

.

Substitute the values of and in above equation.

watts.

The power consumption of the lamp is  watts.

(b)

Find the resistance of the DVD player.

Current .

Power watts.

Solve for .

Consider .

Substitute the values of and in above equation.

The resistance of the DVD player is .

(c)

Ohms law :

Ohms law states that the current through a conductor between two points is directly proportional to the potential difference across the two points.

Ohms law expresses voltage in terms of current and resistance. The two functions are  and .

Solve for .

Consider .

Substitute in equation (1).

(a) The power consumption of the lamp is  watts.

(b) The resistance of the DVD player is .

(c) .

TESTIMONIALS
 "I want to tell you that our students did well on the math exam and showed a marked improvement that, in my estimation, reflected the professional development the faculty received from you. THANK YOU!!!" June Barnett "Your site is amazing! It helped me get through Algebra." Charles "My daughter uses it to supplement her Algebra 1 school work. She finds it very helpful." Dan Pease
 Tweets by @mathskeydotcom

QUESTIONS? LET US HELP.
 Simply chose a support option JOIN US ON:
mathskey.com is not affiliated with any Publisher, Book cover, Title, Author names appear for reference only