Y2_T4_LSN4.2

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

KWIZL: ET_Y2_4.1

§4.2 Speed

p. 162-165

ex 12-21 p 166-171

§4.2 - Learning Goals:

• I can describe the concept of speed and understand which measurements and units are necessary to calculate it.
• I can calculate the speed (or distance or time) of an object using the speed formula.
• I can convert speed between the units of m/s and km/h.   
• I can create and interpret s,t-diagrams relating to an object’s motion. 

P.162-165

§4.2 - Keywords:

• Speed
• s,t-diagram

P.162-165

Speed:

The speed (velocity) of an object tells us how far something moves in a given amount of time. It is calculated with this formula:

P.162-165

Calculating time & distance:

If you know the speed (v) you can also calculate the time (t) or distance (s) with these formulas

• s = v ᐧ t (distance = speed * time)

• t = s/v (time = distance/speed)

P.162-165

Units:

calculated in m/s or km/h.

make sure that your measurements are either: 

meters and seconds

kilometers and hours

P.162-165

Converting units:

It is often useful to convert from m/s ↔ km/h

This can be done by either multiplying or dividing by 3.6

P.162-165

Tom rides his bike to school. Look at the graph from point A until he arrives at school.
What is his average speed in km/h?
And in m/s?

A sprinter runs a 200 m race with a speed of 9.3 m/s. How long did it take her?

Graphing changes in motion:

A graph is an easy way to show an objects changing motion over time. Take a look at the example below:

P.162-165

Hw for lesson 2:

• Complete exercises 12-21 of §4.2 pages 166-171
• Read §4.3 pages 172-175
• Study the glossaries of §4.1-§4.3 on Studygo.

• Entry ticket §4.1 & §4.2
• hw check exercises: §4.1, §4.2 & forces worksheet (3 stickers)

P.154-157