4. Determine the magnitude and direction of acceleration of a system composed of a 4kg cast iron block and a 3kg steel block connected by a pulley. The two blocks are placed on each side of a 2-sided brass inclined plane. The cast iron is placed on the 20-degree side, while the steel is placed on the 45-degree side of the inclined. The coefficients of kinetic friction for cast iron and steel on brass are 0.30 and 0.44 respectively. The static coefficients of friction are 0.40 for cast iron on brass and 0.50 for steel on brass.

4. Determine the magnitude and direction of acceleration of a system composed of a 4kg cast iron block and a 3kg steel block connected by a pulley. The two blocks are placed on each side of a 2-sided brass inclined plane. The cast iron is placed on the 20-degree side, while the steel is placed on the 45-degree side of the inclined. The coefficients of kinetic friction for cast iron and steel on brass are 0.30 and 0.44 respectively. The static coefficients of friction are 0.40 for cast iron on brass and 0.50 for steel on brass.