Question

two masses of 7kg and 3 kg respctvly r hangng on pully.calculate acclration due to gravity....

Answer 1

Two masses of $7\mathrm{kg}$ and $3\mathrm{kg}$ respectively hanging on pulley. Calculate acceleration due to gravity.

Answer on Question#36741 - Physics - Mechanics

The net force acting on the system is the difference between weights of two objects:

$$F_{net} = W_1 - W_2 = m_1 g - m_2 g = (m_1 - m_2) g,$$

where $m_1 = 7\, \text{kg}, m_2 = 3\, \text{kg}, g = 10\, \frac{\text{m}}{\text{s}^2}$.

Total mass of the system

$$M = m_1 + m_2.$$

According to the Newton’s second law acceleration due to gravity is

$$a = \frac{F_{net}}{M} = \frac{(m_1 - m_2) g}{m_1 + m_2} = 10\, \frac{\text{m}}{\text{s}^2} \cdot \frac{7 - 3}{7 + 3} = 4\, \frac{\text{m}}{\text{s}^2}.$$

Answer: $4\, \frac{\text{m}}{\text{s}^2}$.