IB Physics-Topic 2 Mechanics-QC#11-Newton's laws conservation of momentum- A girl on a sledge

Solution of IB Physics past papers questions .
Qc#7: A girl on a sledge is moving down a snow slope at a uniform speed.
a. Draw the free-body diagram for the sledge at the position shown on the
snow slope.
b. After leaving the snow slope, the girl on the sledge moves over a
horizontal region of snow. Explain, with reference to the physical origin
of the forces, why the vertical forces on the girl must be in equilibrium as she
moves over the horizontal region.
c. When the sledge is moving on the horizontal region of the snow, the girl
jumps off the sledge. The girl has no horizontal velocity after the jump. The
velocity of the sledge immediately after the girl jumps off is 4.2 m s . The mass of the girl is 55 kg and the mass of the sledge is 5.5 kg. Calculate the speed of the sledge immediately before the girl jumps from it.
d. The girl chooses to jump so that she lands on loosely-packed snow
rather than frozen ice. Outline why she chooses to land on the snow
e. The sledge, without the girl on it, now travels up a snow slope that makes an
angle of 6.5˚ to the horizontal. At the start of the slope, the speed of the sledge is 4.2 m/ s^2 . The coefficient of dynamic friction of the sledge on the snow is 0.11.Show that the acceleration of the sledge is about –2 m/s^2.
Topic 2- Paper2- mechanics-playlist:

[Nikita-wwop]

THERE IS A MISTAKE FOR THE LAST QUESTION AT 13:14. For the x component it is not -fgcos(theta) it is -fgsin(theta)

[julianvalencia]

HOW DID YOU GET -2.2, the way you did it is wrong, because it gives you -9.76