Bantu jawab pakai cara soal nomor 15-18

15][
m = 50 kg
g = 10 m/s²
a = 2 m/s², ke atas
N = __?

berat semu
ΣF = m a
N - mg = m a
N = mg + ma
N = m (g + a)
N = 50 (10 + 2)
N = 600 N ← jwb
atau
massa semu 60 kg


16][
m = 2 kg
vo = 10 m/s
F = 10 N
S = 10 m
Ekt = __?

Energi kinetik
W = ∆Ek
F S = Ekt - Eko
F S = Ekt - ½ m vo²
10 • 10 = Ekt - ½ • 2 • 10²
100 = Ekt - 100
Ekt = 200 J ← jwb


17][
m = 4 kg
g = 10 m/s²
h = 10 m
W = __?

usaha oleh gaya berat
W = m g h
W = 4 • 10 • 10
W = 400 J ← jwb


18][
2 pegas disusun seri
k1 = 4 N/cm
k2 = 2 N/cm
m = 2 kg
g = 10 m/s²
∆x = __?

konstanta susunan seri
ks = k1 • k2 / (k1 + k2)
ks = 4 • 2 / (4 + 2)
ks = 4/3 N/cm

perpanjangan sistem pegas
F = ks ∆x
m g = ks ∆x
∆x = m g / ks
∆x = 2 • 10 / (4/3)
∆x = 20 × ¾
∆x = 15 cm ← jwb

jawaban terampir dibawah