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two blocks are connected by a string that goes over an ideal pulley as shown in the figure. block a has a mass of 3.00 kg and can slide over a rough plane inclined 30.0° to the horizontal. the coefficient of kinetic friction between block a and the plane is 0.400. block b has a mass of 2.77 kg. what is the acceleration of the blocks?

User Yoni Jah
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Final answer:

The acceleration of the system with two blocks connected by a string over a pulley, one on an inclined plane, is calculated using Newton's second law and considering gravitational and frictional forces. It is found by dividing the net force by the total mass, resulting in an approximate value of 0.395 m/s².

Step-by-step explanation:

The student is asking for the acceleration of a system of two blocks connected by a string passing over an ideal pulley. Block A, with a mass of 3.00 kg, is placed on an inclined plane with a 30-degree angle, and the coefficient of kinetic friction (μ_k) is 0.400. Block B has a mass of 2.77 kg. To find the acceleration, we need to apply Newton's second law of motion (F = ma) and take into account both the gravitational and frictional forces acting on Block A.



First, we calculate the gravitational force component for Block A parallel to the incline, which is m * g * sin(θ). For Block A, this is 3.00 kg * 9.81 m/s² * sin(30°) = 14.715 N. Then we find the frictional force, which is μ_k * m * g * cos(θ). For Block A, this amounts to 0.400 * 3.00 kg * 9.81 m/s² * cos(30°) = 10.188 N. Block B only has the gravitational force acting on it in the downward direction, which is 2.77 kg * 9.81 m/s² = 27.1827 N.



Next, we determine the net force acting on the system by subtracting the frictional force and the force due to Block A's weight component from Block B's weight, which gives us 27.1827 N - 14.715 N - 10.188 N = 2.2797 N. Since the blocks are connected, they will have the same acceleration, so we apply Newton's second law: F_net = m_total * a. Here, m_total is the sum of the masses of Block A and Block B, which is 3.00 kg + 2.77 kg = 5.77 kg.



Finally, to find the acceleration, we divide the net force by the total mass: a = F_net / m_total = 2.2797 N / 5.77 kg = 0.395 m/s². Therefore, the acceleration of the blocks is approximately 0.395 m/s².

User Nurikabe
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