3. Two masses, 4.0 kg and 6.0 kg, are connected by a “massless" rope over a "frictionless" pulley as pictured in the diagram. The ramp is inclined at 30.0° and the coefficient of kinetic friction on the ramp is 0.18. 4.0 kg HK =0.18 6.0 kg 300 a. If the rope breaks when the 4.0-kg mass is 3.0 m from the bottom of the ramp, how long will it take for the mass to slide all the way down? Include a new free-body diagram and assume the sliding mass starts from rest. b. Determine the acceleration of the system once it begins to slide. С. Determine the tension in the rope.

1. The man pushes against the stack of four uniform boxes each weighing 20 lb. If P = 10 lb, determine if the boxes (both individually or as a stack) will slip or tip. The coefficient of static friction between each box is μs = 0.6 and between the floor and the bottom box is μ² = 0.4. P 1.5 ft 1.5 ft 5.5 ft 1.5 ft -2 ft- 1.5 ft

4. You are pushing horizontally with a 300 N force on a box that is on an inclined plane as shown. The mass of the box is 30 kg and the incline is at a 25 degree angle off the Fapplied horizontal. The coefficient of kinetic friction between the box and the incline is 0.3, and the coefficient of static friction i 0.4. Assuming the box was at rest at t=0 when the force is initially applied, is the box moving up the ramp, down the ramp, or is it at rest after the force has been applied? 25⁰

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2. A helicopter drops a cable which is attached to a load. The cable is partially reeled in, and the helicopter flies east. Air resistance causes the load to swing backwards such that it makes an angle of 20.0° with the vertical. Draw a FBD of the situation.

3. A car of mass m is traveling along a circular track of radius r with a constant speed v. Determine the minimum coefficient of static friction between the tires and the track required for the car to remain in circular motion if: a. the track is flat. b. the track has an angle

2. A 3500-lb car travels down the 10-degree inclined road at V = 20ft/s. If the driver steps on the brakes, determine how far the tires skid until it reaches a full stop. Coefficient of friction of the road = 0.5.

1. Two blocks are positioned on surfaces, each inclined at the same angle of 42.8 degrees with respect to the horizontal. The blocks are connected by a rope which rests on a frictionless pulley at the top of the inclines as shown, so the blocks can slide together. The mass of the black block is 2.07 kg, and the coefficient of kinetic friction for both blocks and inclines is 0.510. Assume static friction has been overcome and that everything can slide. What is must be the mass of the white block if both blocks are to slide to the LEFT at an acceleration of 1.5 m/s^2? 2. Two blocks are positioned on surfaces, each inclined at the same angle of 49.5 degrees with respect to the horizontal. The blocks are connected by a rope which rests on a frictionless pulley at the top of the inclines as shown, so the blocks can slide together. The mass of the black block is 2.24 kg, and this time there is NO friction. What is must be the mass of the white block if both blocks are to slide to the LEFT at…

9. Two blocks are positioned on surfaces, each inclined at the same angle of 58.3 degrees with respect to the horizontal. The blocks are connected by a rope which rests on a frictionless pulley at the top of the inclines as shown, so the blocks can slide together. The mass of the black block is 3.66 kg, and the coefficient of kinetic friction for both blocks and inclines is 0.460. Assume static friction has been overcome and that everything can slide. What is must be the mass of the white block if both blocks are to slide to the LEFT at an acceleration of 1.5 m/s^2?     2.16 kg     9.99 kg     6.02 kg     3.06 kg