Question

V. V a-particle V.

The sketch above illustrates a technique called Rutherford backscattering spectroscopy (RBS) which is often used to analyze the composition of a material. Here an alpha particle (mass m₁ = 4.002 u) is shot with a speed of v₁ = 6.700×10⁶ m/s at a target atom of mass m₂ = 28.00 u. It collides (not necessarily elastically) and recoils back at an angle of θ = 140.0° relative to its original direction of motion at a speed of v_a = 4.156×10⁶ m/s, into a detector that measures its speed. Find the speed v_b and direction ϕ (in degrees) of the atom after the collision. Note: An atomic mass unit, 1 u = 1.661 × 10^-27 kg

v_b =  with ϕ =

Answer 1

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