Question

A 2 kg block is on a horizontal, frictionless plane. A string is attached to it and then goes over a pulley at the end of the plane. How much mass should you suspend on the other end of the string in order to obtain an acceleration of 3 m/s2?

Answer 1

$\\ \sf\longmapsto T=2a$

• T means tension

$\\ \sf\longmapsto mg=2a$

$\\ \sf\longmapsto (2+m_2)(10)=2(3)=6$

$\\ \sf\longmapsto m_2+2=\dfrac{6}{10}=0.6$

$\\ \sf\longmapsto m_2=0.6+2$

$\\ \sf\longmapsto m_2=2.6kg$