A point mass m1 = 1.3 kg is attached to a massless rod of length L, so that theytogether form a simple pendulum. The pendulum is initially kept still in the horizontal position(One in the figure). On the surface below (B in the figure) there is a block at rest with mass m2 =0.80 kg. This surface is frictionless between B and C, while it acts frictionbetween C and D (see figure). The distance between C and D is 0.30 m. The air resistance isnegligible in this task. The acceleration of gravity is given at g = 9.81 m / s.

(a) The pendulum now releases so that it swings down. Immediately before m1 collides withm2, m1 has a velocity of 3.8 m / s.

i) Draw a free-body diagram for m1 in the downturn with the angle between the pendulumand the vertical is 45?.