Y2_T2_LSN2.3.B

• Science
• Middelbare school
• havo, vwo
• Leerjaar 2

HAVE READY:

Textbook & notebook closed

Macbook on KWIZL

Practice quiz on Kwizl:

• 8 min max practice quiz.
• 7 min max peer review and feedback.
• 5 min max write a reflection in your notebook:
• What mistakes did I make?
• Why were they mistakes?
• What can I do better next time?

TOPIC 2.3

ELECTRICITY

P. 70-77

§2.3 - Learning Goals:

P. 70-77

I can…:

• Calculate the power a device uses with the help of the formula P= U • I.
• Calculate the amount of energy a device uses with the help of the formula E = P • t.
• Explain how energy consumption depends on both the power of a device and the time it's used. 

§2.3 - Key Words:

P. 70-77

• Electricity
• Electrons
• Electrical current (I)
• Ampères (A)
• Voltage (U)
• Volts (V)
• Voltage source
• Power (P)
• Watt (W)
• Energy consumption
• 
  
• 
  

§ 2.3 - Power

The power of a device is the amount of energy it uses every second.

The power is measured in Watts (W)

Watts is also J/s (joules per second)

§ 2.3 - Power

Power can be calculated with the formula:

P = U x I 

• P for Power (in W)
• U for Voltage (in V)
• I for current (in A)

Energy

Power

Time

Voltage

current

I

P

U

E

t

J

W

s

V

A

I

P

U

E

t

The formula is P = U x I
Witch of these is also correct?

1. U = I / P
2. U = P x I
3. U = P / I
4. U = P + I

A device has a battery of 12 V. There is a current going through the device of 5 A. What is the power of this device?

A telephone has a 15 V battery. Its power in low energy mode is 45 W.
What is the current in the telephone?

A water boiler takes 3 minutes to heat the water. It has a power of 2000 W.
How much energy did the boiler use.

1. 6000 J
2. 667 J
3. 0,015 J
4. 360000 J

Homework for next time:

Lablesson:

• Make sure you have most of your data (at least 14 days) collected and ready to use in this lesson.
• I have made at least 3 graphs and have them ready in my spreadsheet or google docs.

Theory lesson:

• Complete the exercise of Topic 2.3 (p.76-77)
• Read Topic 2.4 (p. 78-81)
• Study the glossary of Topic 2.4 on Studygo.

Circuits simulation part 1:

GET READY:

• your Macbook
• Go to KWIZL
• close all other programs