Question

calcule
a- EC= 10j
m=?
V=2m/s

b- EPG=?
m=0.3kg
g=10m/s
h=2m

c-
EPG= 30j
m=1 kg
g= 10m/s
h=?

Answer 1

a)

Ec = 10J
m = ?
V = 2m/s

Ec = mv²/2
10 = m . 2²/2
10 = m . 2
m = 10 / 2
m = 5,0kg

b)

Epg = ?
m = 0.3kg
g = 10m/s
h = 2m

Epg = Ph
Epg = mhg
Epg = 0,3 . 2 . 10
Epg = 3 . 2
Epg = 6J

c)

Epg = 30J
m =1kg
g = 10m/s
h = ?

Epg = Ph
Epg = mgh
30 = 1 . 10 . h
30 = 10h
h = 30 / 10
h = 3m

 Abraços.