Here are the steps to solve the problem.
First, determine the brick’s hodograph and describe its shape with a formula in Cartesian coordinates (this will be needed later). You may find it helpful to consult European Physics Olympiad Problem No 2 from 2023.
Second, express the force exerted by each plate in terms of the given quantities.
Third, express the displacement as an integral of u_y over time: l_y=\int u_y\mathrm dt=\int u_y\frac{\mathrm du_x}{a_x}, where the x-component of the acceleration, a_x, can be expressed in terms of a_0 and the relevant angles.
Fourth, using the hodograph’s formula, express the integrand in terms of either u_x or u_y. Note that integration by parts may be helpful here.
Fifth, solve the integral.
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