Power and Electric Energy

The unit of electrical power is ...

• the watt

• el watio

• the wat

• el vatio

Quina bombeta emetrà més llum?

• Una de 20 W

• Una de 50 W

• Una de 1 W

• Una alimentada amb 220 V i amb una intensitat de 0,1 A

The Power:

• Is the speed with wich a job is executed

• Is the energy done, divided by the time needed to do that work.

• (Electrical Power) = V x I

• All the answers are correct

Si tenemos un enchufe de 10 A. Calcula la máxima potencia del aparato eléctrico que podemos conectar, considerando que el voltaje es de 230 V

• 23 W

• 220 V

• 2,3 kW

• 2200 W

The device that measures the electrical power is the...

• Volt-meter

• Wattmeter

• Ohmmeter

• Reactivity meter

From the expression: 

 $P=\frac{E}{t}$  

We could know...

• ... that energy is the product of power by time

• ... that the time is the product of energy by power

• ... that the power is the product of energy by time

• ... that the power is time divided by energy

Calculate the energy consumed by a heater of 350W in 7 hours of working.

• 50 kWh

• 50 Wh

• 2450 W

• 2,45 kWh

• En ambos circuitos las baterías están en serie

• En el circuito de la izq. las bombillas están conectadas en serie

• En el circuito de la der. las bombillas están conectadas en paralelo

• Todas son correctas.

Calculate the energy in KWh consumed by a heater of 500W in 4 hours of working.

• 2 kW

• 4 kWh

• 2 kWh

• 2 000 kWh

The device that measures the electrical energy consumed is the ...

• wattmeter

• counter

• polímetro

• amperímetro