A block hangs from a spring balance. The balance reads 40 N in air, 35 N when block is immersed in water and 25 N when block is immersed in another liquid. Find the density of block and other liquid.

Explanation

To solve the problem step by step, we will use the principles of buoyancy and the readings from the spring balance.

### Step 1: Understand the Forces Acting on the Block
When the block is hanging in air, the spring balance reads the weight of the block, which is equal to the gravitational force acting on it, \( F_g = mg \). When the block is submerged in a fluid, the spring balance reads less due to the buoyant force acting on the block.

### Step 2: Calculate the Weight of the Block
From the first reading in air:
- Weight of the block \( F_g = 40 \, \text{N} \)
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