A mass M attached to a spring of spring constant 0.7 N/m oscillates on a smooth horizontal table. When displacement is 0.3 m, velocity is 2 `ms^(-1)`. And when displacement is 0.4 m, velocity is 0.3 m/s. Calculate the vlaue of M.

Explanation

To solve the problem, we need to find the mass \( M \) attached to a spring with a spring constant \( k = 0.7 \, \text{N/m} \). We are given two conditions regarding the displacement and velocity of the mass during its oscillation.

### Step-by-Step Solution:

1. **Identify the Given Values**:
- Spring constant, \( k = 0.7 \, \text{N/m} \)
- Condition 1: Displacement \( x_1 = 0.3 \, \text{m} \), Velocity \( v_1 = 2 \, \text{m/s} \)
- Condition 2: Displacement \( x_2 = 0.4 \, \text{m} \), Velocity \( v_2 = 0.3 \, \text{m/s} \)
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