forces - speed

Question 1

what does distance tell us?

Answer 1

how far something has moved

Question 2

what does distance tell us?

Answer 2

the distance an object moves in a straight line from the start point to the finish point. it must include direction of straight line. includes direction + magnitude (vector quantity)

Question 3

what does the speed of an object tell us?

Answer 3

the distance an object travelled in a given time.
it is a scalar quantity as it doesn’t involve direction

Question 4

speed equation

Answer 4

(m/s) = distance (m) / time(s)

Question 5

a) distance symbol
b) speed symbol

Answer 5

a) s
b) v

Question 6

typical speeds:
a) normal walking speed
b) running speed
c) cycling speed

Answer 6

a) around 1.5 m/s
b) around 3 m/s
c) around 6 m/s

Question 7

what do the typical speeds depend on?

Answer 7

• a younger, fitter person will generally be able to achieve a faster speed than an old person or unfit person
• depends on terrain. more faster in flat ground than uphill
• depends on distance travelled. run faster at start when less tired on a long distance run

Question 8

typical speeds:
a) car on main road
b) fast train in UK
c) cruising aeroplane

Answer 8

a) around 13 m/s. rarely constant as a car speeds up + slows down depending on diff journeys
b) around 50 m/s
c) around 250 m/s

Question 9

speed of sound in air? why can this vary?

Answer 9

around 330 m/s
e.g sound travels faster on hotter days than cooler ones

Question 10

what do we tend to calculate in speed questions?

Answer 10

average speed over the total length of journey