Physics, 22.07.2021 16:40 mgarcia1394

A water heater marked 4 kW takes 4 minutes to heat 1 kg of water from 20 °C to 50 °C. The cost of electrical energy per kWh is $0.120. What will be the total cost of energy consumption?

Answers: 1

Show answers

Answers

Answer from: hanjonez

The total cost of the energy consumption for the given time period is $0.0364

The given parameters include;

power rating of the heater, P = 4 kW = 4000 Wtime taken to completely boil the water, $t = 4 \min = 4 \min \times \frac{1 \ h}{60 \ \min} = 0.067 \ h$ mass of the water, m = 1 kginitial temperature of the water, t₁ = 20 ⁰Cfinal temperature of the water, t₂ = 50 ⁰Cspecific heat capacity of water, c = 4200 J/kg⁰Ccost of electrical energy = $0.12

The total energy consumed in the process of heating the water;

Total electrical Energy = Energy of the heater (kWh) + Energy of the heated water (kWh)

Energy of the heater (kWh) = power x time

= 4 kW x 0.067 h

= 0.268 kWh

Energy of the heated water (J) = mcΔt

where;

Δt is the change in temperature = t₂ - t₁

= 50 ⁰C - 20 ⁰C = 30⁰C

Energy of the heated water (J) = 1 x 4200 x 30

= 126,000 J

Electrical power of the heated water (Watts) = $\frac{126,000 \ J}{4 \ \min} \times \frac{1 \min}{60 \ s} = 525 \ W$

Energy of the heated water (kWh) = $\frac{525}{1000} \times 4\min\times \frac{1 \ hr}{60 \min} = 0.035 \ kWh$

Total electrical Energy = 0.268 kWh + 0.035 kWh

= 0.303 kWh

The total cost of the energy consumed is calculated as;

$Total \ cost = \frac{\$ \ 0.12}{kWh} \times 0.303 \ kWh = \$ \ 0.0364$

Therefore, the total cost of the energy consumption is $0.0364

To learn more about cost of electrical energy calculation, please visit:

Answer from: Quest

explanation:

i think the answer is d. but im not sure!

Answer from: Quest

Answerthe energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.explanationwe define electric potential as the ratio electric potential energy to the charge, $v = \dfrac{e_p}{q}$ then the following gives us the potential difference, $\delta v = v_b - v_a$ $\begin{aligned} \delta v & = \dfrac{e_p_b}{q} - \dfrac{e_p_a}{q} \\ & = \dfrac{\delta e_p}{q} \end{aligned}$ the formula $\delta v = \delta e_p / q$ may be on your formula sheet.the change in electric potential energy would be the energy that would needed to move it from point a to point b. solving for that, we get $\delta e_p = q\delta v$ using q = 8.00 × 10⁻¹⁹ c and δv = 2.00 v, we get $\begin{aligned} \delta e_p & = (8.00\times10^{-19} \text{ c})(2.00\text{ v}) \\ & = 1.60\times 10^{-18}\text{ j} \end{aligned}$ the energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.

Another question on Physics

Physics, 22.06.2019 06:30

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant

Answers: 1

Answer

Physics, 22.06.2019 08:30

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

Answers: 2

Answer

Physics, 22.06.2019 09:00

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy

Answers: 2

Answer

Physics, 22.06.2019 09:30

The graph represents the distance a car travels over time while on the highway. which statement about the car's trip is accurate? a) the car does not move over time. b) the car travels at a constant velocity. c) the car's velocity increases constantly over time. d) the car's velocity decreases constantly over time.

Answers: 1

Answer

You know the right answer?

A water heater marked 4 kW takes 4 minutes to heat 1 kg of water from 20 °C to 50 °C. The cost of el...

Questions