Tolong di jawab pliss.

1.
Diketahui
r = 2 m
f = 120 rpm = 120 / 60 Hz = 2 Hz

Ditanya
v = ...?

Jawab
v = 2π . r  . f
   = 2π . 2 . 2
   = 8π m/s

2.
Diketahui
n = 30 putaran
t = 15 detik
r = 50 cm = 0,5 m

Ditanya
f = ...?
T = ...?
as = ...?

Jawab
f = n / t = 30 / 15 = 2 Hz
T = 1/f = 1/2 = 0,5 s

v = 2π . r . f = 2π . 0,5 . 2 = 2π
as = v²/r = (2π)² / 0,5
     = 8π² m/s²

3. 
Diketahui
m = 5 kg
v = 2 m/s
r = 50 cm = 0,5 m

Ditanya
T = ...?
as = ...?

Jawab
v = 2π r / T
T = 2πr / v
   = 2π . 0,5 / 2
   = π/2 s

as = v² / r = 2² / 0,5 = 8 m/s²