Answer:
1.8 x 10⁻³⁴ m.
Step-by-step explanation:
de Broglie wavelength ( λ ) of a moving particle is given by the following expression
λ = h / momentum of the particle
In other words, de Broglie wavelength depends upon the momentum of the particle.
In the given case , particle A which is stationary collides with another particle B having some momentum . After the collision , they move together.No external force acts on them . Therefore after the collision , their momentum will be conserved. In other words , their momentum remains the same as earlier. So their de Broglie wave length will also be the same as earlier , since it depends on the momentum of the moving body.
Hence the de Broglie wavelength of the object will be 1.8 x 10⁻³⁴ m.