Lernkarten

Karten 20 Karten 1 Lernende English Mittelschule 30.11.2015 / 30.11.2015 Keine Angabe
0 Exakte Antworten 20 Text Antworten 0 Multiple Choice Antworten

What quantities describe motion?

displacement s

velocity v

acceleration a

Symbol and SI unit: displacement

Symbol: s

SI unit: m (meter)

Symbol, definition, SI unit: velocity

Symbol: v

definition:  v = delta s/delta t    --> v=? const. or av. velocity

SI unit: ms-1

Symbol, definition SI unit: Acceleration

symbol: a

definition: a= delta v/delta t   --> a=const. or av. acceleration

si unit: ms-2

What can be read from an s-t-graph? How is it done?

- exactly one displacement s for each time t

- velocity v by: - the slope (for straight lines): v = delta s/delta t

- the slope of the tangent: v = limit of delta t aproaching 0 delta s/delta t

What can be read from an v-t-graph? How is it done?

- exactly one velocity v for ach time t

- acceleration a bvy the slope (of a straight line): a= delta v/delta t

- change in displacement delta s by the area under the curve

km/h: What quantity has km/h as unit? How is km/h converted to the si-unit?

- velocity or speed

- 1 km h-1 = 1000m/1h = 1000m/3600s = 1/3.6 s-1

What does free fall mean and by which quantity is it described? State its symbol, value and si-unit.

A body falls freely if it falls without friction (or friction is negligible). In this case, its motion is uniformly accelerated with acceleration a=g. The quantity g descibes the free fall and is called free-fall acceleratin or gravitational acceleration.

- symbol: g

-value: g= 9.81 m s-2  --> at the surface of the earth

- si unit: ms-2