Work, Energy and Power · Question 1

In a scattering experiment, a particle of mass 2m collides with another particle of mass m, which is initially at rest. Assuming the collision to be perfectly elastic, the maximum angular deviation of the heavier particle, as shown in the figure, in radians is: [figure]

2. -1 ( 12 )
3. 3
4. 6

Answer

(4) 6

Solution

For an elastic collision of m1 with m2 at rest (m1>m2), the maximum deflection of m1 is given by max= m2m1.

(In the CM frame the speed of m1 is uc= m2um1+m2 and the CM speed is V= m1um1+m2; the lab deflection is maximum when the final velocity is tangent to the circle of radius uc, so max= ucV= m2m1.)

max= m2m= 12 max= 6

Answer: (D)