Question

Oblicz pole powierzchni bocznej i pole powierzchni całkowitej prostopadłościanu. a) 10 cm 18 cm 5 cm

Pb = ................................................................. Pc=.............................................................................

b) 35mm 2,6 cm , 2,6 cm

Pb=............................................... Pc=......................................................

Answer 1

a)

a = 10cm

b = 18cm

h = 5cm

Pb = 2 * (a * h) + 2 * (b * h)

Pb = 2 * (10 * 5) + 2 * (18 * 5)

Pb = 2 * 50 + 2 * 90

Pb = 100 + 180

Pb = 280cm² 

Pc = 2 * Pp + Pb

Pp = a * b = 10 * 18 = 180cm² 

Pc = 2 * 180 + 280

Pc = 360 + 280

Pc = 640cm²

 

 b)

a = 3,5cm

b = 2,6cm

h = 2,6cm 

 

Pb = 2 * (a * h) + 2 * (b * h) 

Pb = 2 * (3,5 * 2,6) + 2 * (2,6 * 2,6)

Pb = 2 * 9,1 + 2 * 6,76

Pb = 18,2 + 13,52

Pb = 31,72cm² 

 

Pc = 2 * Pp + Pb

Pp = a * b = 3,5 * 2,6 = 9,1cm² 

Pc = 2 * 9,1 + 31,72

Pc = 18,2 + 31,72

Pc = 49,92cm²

Answer 2

a)

Pb=(10cm*5cm)*2+(18cm*5cm)*2=50cm2*2+90cm2*2=100cm2+180cm2=280cm2

Pc=Pb+Pp=280cm2+(10cm*18cm)*2=280cm2+180cm2*2=280cm2+360cm2=640cm2

 

b)                                       35mm=3,5cm 

Pb=(3,5cm*2,6cm)*2+(2,6cm*2,6cm)*2= 9,1cm2*2+6,76cm2*2=18,2cm2+13,52cm2=      31,72cm2

Pc=Pb+Pp=31,72cm2+(3,5cm*2,6cm)*2=31,72cm2+9,1cm2*2=31,72cm2+18,2cm2=49,92cm