A block of mass 4 kg is suspended through two light spring balances A and B connected in series. Then A and B

Question

A block of mass 4 kg is suspended through two light spring balances A and B connected in series. Then A and B will read respectively:

Accepted Answer

1. **System Configuration:** When two light (massless) spring balances are connected in series (one suspended from the other) supporting a mass, the tension is uniform throughout the chain.
2. **Free Body Diagram:** 
   - For the block: The downward force is weight $W = mg = 4g$. The upward force is the tension in Balance B ($T_B$). For equilibrium, $T_B = 4g$. Balance B reads $4$ kg.
   - For Balance B: It is massless. It is pulled down by tension $T_B$ and pulled up by tension from Balance A ($T_A$). For equilibrium, $T_A = T_B = 4g$. Balance A reads $4$ kg [Source 41].
3. **Newton's Third Law:** The action and reaction forces are equal and opposite. The force transmitted through the series of massless springs is equal to the load suspended.
4. **Conclusion:** Both spring balances measure the same tension corresponding to the mass of the block.

Step-by-Step Solution

Practice All PHYSICS Questions