Following results are observed when sodium metal is irradiated with different wavelength. Calculate (a) threshold wavelength and (b) Planck's constant
`{:(,lambda(nm),500,450,400),(,v xx 10^(-5)(cms^(-1)),2.55,4.35,5.35):}`

Explanation

To solve the problem, we will follow these steps:

### Step 1: Understand the Given Data
We have the following data for sodium metal when irradiated with different wavelengths:
- Wavelengths (in nm): \( \lambda_1 = 500 \), \( \lambda_2 = 450 \), \( \lambda_3 = 400 \)
- Velocities (in \( \text{cm/s} \times 10^{-5} \)): \( v_1 = 2.55 \), \( v_2 = 4.35 \), \( v_3 = 5.35 \)

### Step 2: Convert Wavelengths to Meters
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