Question

problema 57 va rogg. dau coroana

Answer 1

pt.m1:Vectorial:T+N1+G1+Ff1=m1a

Scalar:Ox:T-Ff1=m1a

           Oy:N1-m1g=0=>N1=m1g

Ff1=μN1=μm1g

T-μm1g=m1a  (1)

pt.m2:Vectorial:T+N2+G2+Ff2=m2a

Scalar:Ox:m2gsinα-Ff2-T=m2a

          Oy:N2-m2gcosα=0=>N2=m2gcosα

Ff2=N2=μm2gcosα

m2gsinα-μm2gcosα-T=m2a  (2)

(1)+(2)=>g(m2sinα-μm2cosα-μm1)=(m1+m2)a=>a=g(m2sinα-μm2cosα-μm1)/(m1+m2)

T=m1(a+μg)

Vectorial:R+T1+T2=0=>R=-(T1+T2=>R²=T1²+T2²+2T1T2cos(180°-α) (pui vectori pe toate literele)

Scalar:T1=T2=T=m1g=>R²=2T²-2T²sinα=>R=T√(2(1-sinα))

a=0=>m1=m2(sinα-μcosα)/μ

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