Question

3.stosunek objetośći 2kul jest równy 27:1.oblicz stosunek pól tych kul

Answer 1

V1/V2=27/L

V1/V2=k do 3 potegi

k3=27/1

k=3/1

P1/P2=k2=(3/1)do2 potegi=9/1

stosunek pól wynosi 9 :1

 

Answer 2

kuk\la 1

kula 2

                       V₁       27               P₁

                      ---- = -----             ---- = ?

                       V₂        1               P₂

 

                       V=4/3·πr³

 

                      V₁=27 V₂

                      4/3·πr³₁=27· 4/3·πr₂³  |:4/3·π

 

                        r₁³=27 r₂³             P=4πr²   P₁=4πr₁²  P₂=4πr₂²

 

                        r₁=∛27r₂³

 

                        r₁=3r₂      

 

                                              P₁        4πr₁²      r₁²     (3r₂)²     9 r₂²      9

                                             ------  = ------ = ----- = -------  =  ------  = ----

                                              P₂        4πr₂²      r₂²       r₂²         r₂²       1

 

 

stosunek pół tych kul wynosi 9:1