Question

Two bodies of masses 4 kg and 3 kg respectively are connected by a light string passing over a smooth frictionless pulley. Calculate the acceleration of the masses and tension in the string.

Answer 1

Constraint Equation:

\(a_{m_1} + a_{m_2} = 0\). [\(\because\) length of string is constant]

Let us say m₁ moves down with an acceleration ‘a’, then m₂ will move up by an acceleration ‘a’.

m₁g – T = m₁a   …(i)

And using this value, find the value of T in equation (i) or equation (ii)

m₁g – m₁a = T

⇒ T = m₁(g – a)

Now put m₁ = 4 kg m₂ = 3kg

To get the numerical, after putting values of m₁, m₂ and a 

⇒ T = m₁(g − a) = 33.6 N