Question

Find the reading of the massless spring balance in the given condition

Answer 1

according to the diagram,

there is a 2kg block on the left hand side and 3kg block on the right hand side. the two forces will try to pull the other toward it self as they are connected by a non stretchable cord and then a spring balance.

Now you must be very well aware of the fact that the reading of the spring balance will be equal to the tension in the cord.

Force by 2kg = m1 = weight of 2kg = m1 * g = 2 * 10 = 20N

Force by 3kg = m2 = weight of 3kg = m2 * g = 3 * 10 = 30N

the net force = FR = 30N - 20N = 10N

the total mass of the system = M = 2+3 = 5kg

the acceleration of the system = FR/M = 10N/5 = 2m/s

{We are calculating the tension with respect to 2kg block, will be easier, and we'll get the same answer}

here,

T - m2 * g = m2 * a

T = m2 *a + m2 * g

T = 2*2 + 2*10

T = 24N