Question

Tolong dong diajarin caranya

Answer 1

Kita cari dulu konstanta gabungan pegas. 
(1) kp1 = 150+150 = 300 N/m
kp2 = 200+100 = 300 N/m
1/ks = 1/300+1/300+1/100
 = 1+1+3/300 = 5/300
ks = 300/5 = 60 N/m

F = kx
m.g = kx
0,2.10 = 60x
x1 = 2/60

(2) kp1 = 100+100+150 = 350 N/m
kp2 = 200+100 = 300 N/m

1/ks = 1/350+1/300 =  300+350/105000
ks = 105000/650 = 161,5 = 162 N/m

F = kx
m.g = kx
0,2.10 = 162 x
x = 2/162

Perbandingan pertambahan panjang:
x1/x2 = 2/60 : 2/162
 = 2/60.162/2 = 162/60 = 27/10

*dicek lagi angkanya mungkin ada salah lihat soalnya tulisannya kecil, nanti disesuaikan jawabannya.

Ep (2) = 1/2.F.x
          = 1/2.2.2/162 = 0,012 J

Ep (1) = 1/2.F.x = 1/2.2.2/60 = 0,033 J