6. Three blocks of masses m₁, m2, and m3 are placed in contact with each other on a frictionless, horizontal surface, as shown in the figure below. A horizontal foce F is applied to m₁. Take 2.00 kg, m2 = 3.00 kg, m3 4.00 kg, and F m1 = = 18.0 N. (a) Draw a separate free-body diagram for each block. (b) Determine the acceleration of the blocks. (c) Find the resultant force (that is, the net force) on each block. (d) Find the magnitude of the contact forces between the blocks. m1 mq mz

Two teams of nine members each engage in tug-of-war. Each of the first team’s members has an average mass of 68 kg and exerts an average force of 1350 N horizontally. Each of the second team’s members has an average mass of 73 kg and exerts an average force of 1365 N horizontally. (a) What is magnitude of the acceleration of the two teams, and which team sins? (b) What is the tension in the section of rope between the teams?

(a) Find an equation to determine the magnitude of the net force required to stop a car of mass m, given that the initial speed of the car is v0 and the stopping distance is x . (b) Find the magnitude of the net force if the mass of the car is 1050 kg, the initial speed is 40.0 km/h, and the stopping distance is 25.0 m.

(a) A cat with a mass of 850 kg in moving to the right with a constant speed of 1.44 m/s. What is the total force on the cat ? (b) What is the total force on the cat if it is moving to the left?

(a) What is the maximum frictional force in the knee joint of a person who supports 66.0 kg of her mass on that knee? (b) During strenuous exercise, it is possible to exert forces to the joints that are easily 10 times greater than the weight being supported. What is the maximum force of friction under such conditions? The frictional forces in joints are relatively small in all circumstances except when the joints deteriorate, such as from injury or arthritis. Increased frictional forces can cause further damage and pam.

Two forces F1=(62.98i15.80j) N and F2=(23.66i78.05j) are exerted on a particle. The particles mass is 14.23 kg. a. Find the particles acceleration in component form. b. What are the magnitude and direction of the acceleration?

A car of mass 875 kg is traveling 30.0 m/s when the driver applies the brakes, which lock the wheels. The car skids for 5.60 s in the positive x-direction before coming to rest. (a) What is the cars acceleration? (b) What magnitude force acted on the car during this time? (c) How far did the car travel?

(a) What force causes an automobile to move? (b) A propeller-driven airplane? (c) A rowboat?

Consider the 65.0-kg ice skater being pushed by two others shown in Figure 5.21. (a) Find the direction and magnitude of Ftot, the total force exerted on her by the others, given that the magnitudes F1and F2are 26.4 N and 18.6 N, respectively. (b) What is her initial acceleration if she is initially stationary and wearing steel-bladed skates that point in the direction of Ftot? (c) What is her acceleration assuming she is already moving in the direction of Ftot? (Remember that friction always acts in the direction opposite that of motion or attempted motion between surfaces in contact.)

(a) Why does an ordinary rifle recoil (kick backward) when fired? (b) The barrel of a recoilless rifle is open at both ends. Describe how Newton’s third law applies when one is fired. (c) Can you safely stand close behind one when it is fired?