Question

w swobodnym spadku cieło uderza w ziemię z V=36km/h.

oblicz z jakiej wysokości spało i w jakim czasie?

Answer 1

v = 36km/h = 10m/s

h = v²/2g

h = (10m/s)²/2 x 10m/s² = 5m

 

s = at²/2 --> t=√2s/a

t = √2 x 5m/10m/s² = 1s

 

Pozdrawiam Marco12 ;)

Answer 2

dane:

v = 36 km/h = 36 *1000m/3600s = 10 m/s

g = 10 m/s2

szukane:

h = ?

t = ?

                                /

Z zasady zachowania energii:

  Ep = Ek

mgh = mv^2 /2  /:m

gh = v^2 /2   I*2

2gh = v^2  /:2g

h = v^2 /2g

h = (10m/s)^2 /(2*10m/s2)

h = 5 m

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v = gt  /:g

t = v/g

t = 10m/s /10m/s2

t = 1 s

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