The block of mass m2 in the figure has been adjusted so that the block of mass m, is on the verge of sliding. (a) If m¡ = 7 kg and m, = 5 kg , what is the coefficient of static friction between the table and the block? (b) With a slight nudge, the blocks move with acceleration of magnitude a. Find a if the coefficient of kinetic friction between the table and the block is µk = 0.54 %3D m2

A block of mass 57.1 kg rests on a slope having an angle of elevation of 24.3°. If pushing downhill on the block with a force just exceeding 182 N and parallel to the slope is sufficient to cause the block to start moving, find the coefficient of static friction.

Two blocks of mass M| and M2 are connected by a massless string that passes over a massless pulley as shown in the figure. M1 has a mass of 3.75 kg and rests on an incline of 0 = 57.5°. M2 rests on an incline of 02 = 19.5°. Find the mass of block M2 so that the system is in equilibrium (i.e., not accelerating). All surfaces are frictionless. M, M2 = kg Figure is not to scale.

A block of mass 53.1 kg rests on a slope having an angle of elevation of 20.3°. If pushing downhill on the block with a force just exceeding 162 N and parallel to the slope is sufficient to cause the block to start moving, find the coefficient of static friction.

(a) What is the coefficient of kinetic friction between the crate and the floor? (Enter your answer to at least three decimal places.) (b) If the 250-N force is instead pulling the block at an angle of 20.0° above the horizontal, as shown in the figure b, what will be the acceleration of the crate? Assume that the coefficient of friction is the same as that found in part (a). m/s2

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A block of mass m1 = 3.41 kg on a frictionless plane inclined at angle 0 = 26.1° is connected by a cord over a massless, frictionless pulley to a second block of mass m2 = 2.37 kg hanging vertically (see the figure). (a) What is the acceleration of the hanging block (choose the positive direction down)? (b) What is the tension in the cord? %3D (a) Number i Units (b) Number i Units > >

Two children are fighting over a toy box of mass   kgm=35.0kg in a sand box. Child B pulls at an upward angle of θ=68.0° with force   NFB​=56.0N while Child A pulls on the other side horizontally with a force ��FA​. If the coefficient of static friction between the box and sand is μs​=.342 how much force must Child A pull with in order to just start moving the box in their direction? Pick the correct answer

Two teams of nine members each engage in a tug of war. Each of the first team’s members has an average mass of 61 kg and exerts an average force of 1359 N horizontally. Each of the second team’s members has an average mass of 73 kg and exerts an average force of 1363 N horizontally.  (a) What is the acceleration of the two teams? Give this as a positive value. (b) What is the tension in the section of rope between the teams?

Two packing crates of masses m, = 10.0 kg and m, = 4.90 kg are connected by a light string that passes over a frictionless pulley as in the figure below. The 4.90-kg crate lies on a smooth incline of angle 37.0°. Find the following. m2 m, (a) the acceleration of the 4.90-kg crate m/s? (up the incline) (b) the tension in the string