IB Physics-Paper2-Theme D2-Qc#8 Momentum and Electric field

This question is in two parts. Part 1 is about momentum. Part 2 is about electric point charges.
Part 1 Momentum
a. State the law of conservation of linear momentum.
b. A toy car crashes into a wall and rebounds at right angles to the wall,
as shown in the plan view.
The graph shows the variation with time of the force acting on the car due to the wall during the collision.
The kinetic energy of the car is unchanged after the collision. The mass of the car
is 0.80 kg.
(i) Determine the initial momentum of the car.
(ii) Estimate the average acceleration of the car before it rebounds.
(iii) On the axes, draw a graph to show how the momentum of the car varies
[9 marks]
c. Two identical toy cars, A and B are dropped from the same height onto
a solid floor without rebounding. Car A is unprotected whilst car B is in a
box with protective packaging around the toy. Explain why car B is less likely to be damaged when dropped. during the impact. You are not required to give values on the y-axis.
Part 2 Electric point charges
Define electric field strength at a point in an electric field.
e. Six point charges of equal magnitude Q are held at the corners of a
hexagon with the signs of the charges as shown. Each side of the
hexagon has a length a.
P is at the centre of the hexagon.
(i) Show, using Coulomb’s law, that the magnitude of the electric field strength at
point P due to one of the point charges is
(ii) On the diagram, draw arrows to represent the direction of the field at P due to point charge A (label this direction A) and point charge B (label this direction B).
(iii) The magnitude of Q is 3.2 μC and length a is 0.15 m. Determine the
magnitude and the direction of the electric field strength at point P due to all six charges.
Topic 5 Electricity playlist
Topic 2 mechanics