Maaf ya buatt yg jwb krna bnyk bgt hehe :D tpi tenang point nya jga bnyk kok ;) gambar 1. no 25 gam.... Question from @chikajessicaa

September 2018 1 66 Report

Maaf ya buatt yg jwb krna bnyk bgt hehe :D
tpi tenang point nya jga bnyk kok ;)
gambar 1. no 25
gambar 2 . no 5,6,7
gambar 3 no 1 smpai 5

geniusgyu Gambar 1
tinggi t = 42 cm
jari-jari r = 21 cm
Volume udara :
$V_{udara} =V_{tabung}-V_{bola}$
$V_{udara}= \pi r^{2} t- \frac{4}{3} \pi r^{3}$
$V_{udara}= \frac{22}{7} (21^{2} )(42) - ( \frac{4}{3} )( \frac{22}{7} )( 21^{3} )=58.212-38.808=19.404cm^{3}$
jawaban (b)

Gambar 2 no.5
volume V = 2.310 L = 2.310 dm³
jari-jari r = 70 cm = 7 dm
tutup tabung:
$V= \pi r^{2} t$
$2.310 = ( \frac{22}{7} )( 7^{2} )t$
t = 15 dm
Luas permukaan tabung tanpa tutup :
$L= \pi r(r+2t)$
$L= (\frac{22}{7} )(7)(7+2(15))=814 dm^{2}$
jawaban (c)

Gambar 2 no.6
jari-jari r = 10 cm
tinggi t = 20 cm
volume tabung :
$V= \pi r^{2} t$
$V=(3,14)( 10^{2} )(20)=6280 cm^{3}$
jawaban (c)

Gambar 2 no.7
jari-jari r = 5 cm
tinggi t = 21 cm
terisi air 1/3 bagian, maka volume air :
$V_{air} = \frac{1}{3} V_{tabung}= \frac{1}{3} (\pi r^{2} t)$
$V_{air}=( \frac{1}{3}) ( \frac{22}{7} )(5^{2})(21)=550 cm^{3}$
jawaban (d)

Gambar 3 no.1
diameter d = 21 cm
tinggi t = 24 cm
volume kaleng kecil Vk = 250 cm³
volume minyak :
$V_{minyak}= \frac{1}{4} \pi d^{2}t=( \frac{1}{4} )( \frac{22}{7} )(21^{2})(24)=8.316cm^{3}$
banyak kaleng yang dibutuhkan = volume minyak : volume kaleng kecil
= 8.316 : 250 = 33,264kaleng

Gambar 3 no.2
tinggi topi tidak ikut terfoto

Gambar 3 no.3
Luas selimut L = 1.177,5 cm²
jari-jari r = 15 cm
(a). panjang garis pelukis s :
L = πrs
1.177,5 = (3,14) (15) s
s = 25 cm
(b). luas permukaan :
L = πr (r+s)
L = (3,14) (15) (15 + 25)
L = 1.884 cm²

Gambar 3 no.4
diameter d = 7 dm
(a). luas permukaan
L = 4πr²
L = 4 (22/7) (7/2)²
L = 154 dm²
(b). volume
V = (4/3)πr³
V = (4/3) (22/7) (7/2)³
V = 179,67 dm³

Gambar 3 no.5
panjang total p = 17 cm
diameter d = 6 cm, maka jari-jari r = 3cm
tinggi kerucut t(k) = 4 cm
maka, tinggi tabung t(t) = p - t(k) = 17 - 4 = 13 cm
Volume bangun :
V = V(tabung) + V(kerucut)
V = πr²t(t) + (1/3)πr²t(k) = πr² (t(t) + t(k)/3)
V = (3,14) (3²) (13 + (4/3))
V = 405,06 cm³

2 votes Thanks 2

chikajessicaa tinggi topi 35 cm

geniusgyu (Gb.3 no.2) garis pelukis s = (r^2 + t^2)^(1/2) = (12^2 + 35^2)^(1/2) = 37 cm

geniusgyu Luas permukaan = (pi)r (r+s) = (3,14)(12)(12+37) = 1.846,32 cm^2

chikajessicaa makasih ka ^_^

geniusgyu u r welcome~