Question

hola tengo un problema AYUDENME
ES LA PREGUNTA 19

Answer 1

Coordenadas:

↑y

|

|

•———→ x

Fórmulas:

m₁ = 3kg

y) T₁ - m₁•g = m₁•a

T₁ = m₁•(a+g)

m₂ = 4kg

y) N - m₂•g = 0

N = m₂•g

x) T₃ - T₁ + | Fr | = m₂•a

m₃ = 10kg

y) T₃ - m₃•g = m₃•a

T₃ = m₃•(a+g)

T₃ - T₁ + | Fr | = m₂•a

m₃•(a+g) - m₁•(a+g) + | Fr | = m₂•a

(a+g)•(m₃ - m₁) + | Fr | = m₂•a

| Fr | = m₂•a - (a+g)•(m₃ - m₁)

Fr = μ•N

Fr = μ•m₂•g

Fr = 0,40•4kg•10m/s²

Fr = 16N

16N = 4kg•a - (a+10m/s²)•(10kg - 3kg)

16N = 4kg•a - (a+10m/s²)•7kg

16N = 4kg•a - 7kg•a - 70N

86N = (4kg - 7kg)•a

86N = -3kg•a

a = -28,667m/s²