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how do i solve this problem?hint: 1. Draw the forces -cart: weight downwards, normal force upwards, tension right and friction leftblock: weight downwards and tension upwards2. The friction on the sliding block can be calculated with f = μN (where μ is the coefficient of kinetic friction and N is the normal force). 3. The combined mass is equal to the two masses (kgs) added together.4. The tensions cancel, as do the weight and normal force of the sliding block, so the net force will equal the weight of the hanging block minus the friction.5. Calculate the acceleration using a = Fnet / m6. The tension can be calculated on the hanging block with T = W - ma (since the block with accelerate downwards) or to the cart with T = f + ma (because the sliding block is accelerating to the right).

how do i solve this problem?hint: 1. Draw the forces -cart: weight downwards, normal-example-1
User UrsaDK
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1 Answer

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A force diagram is shown below:

where,

N: normal force on block1

fg1: weight of block1 = (6kg)(9.8m/s^2) = 58.8N

T: tension in the string

Fr: friction force between the block and the table = μk*N

fg2: weight of block2 = (5kg)(9.8m/s^2) = 49N

Consider that the normal force is equal and opposite to the weight of block1 (becasue the equilibrium of the vertical forces n the block1), then:

N = fg1 = 58.8N

μk: coefficient of kinetic friction = 0.3

Fr = μk*N = (0.3)(58.8N) = 17.64N

Based on the given information and the force diagram, you can conclude:

Four forces are acting on the sliding block.

Two forces are acting on the hanging block.

The forces of the system are unbalanced due to the weight of the hanging block.

The magnitud of the friction force is 17.64N

The mass of the system is the sum of the masses of the blocks:

mass of the system = 6kg + 5kg = 11kg

The net force is, based on the clarification of point 4:

Fnet = fg2 - Fr = 49N - 17.64N = 31.36N

The acceleration of the system is:

a = 31.36N/(11kg) = 2.85 m/s^2

After release the sliding block moves to the right.

The tension in hte string is calculated by using the sum of forces on the sliding block:

T = Fr + m1*a

T = 17.64N + (6kg)(2.85m/s^2) = 17.64N + 17.1N = 34.74N

how do i solve this problem?hint: 1. Draw the forces -cart: weight downwards, normal-example-1
User Hangy
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