HW2 full solution with detailsand steps pictures PDF

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HW2 full solution with details and steps pictures...

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Homework2 Note: Since Mastering Physics randomizes numerical parameters, their values in this solution may be different from those you have for your homework assignment in Mastering Physics. Parameters in this solution follow those printed in the textbook. 4.14 A 4.35 kg cat moves in a straight line (the x-axis). shows a graph of the x-component of this cat's velocity as a function of time.

（a） Find the maximum net force on this cat. （b） When does the maximum net force on this cat occur? （c） When is the net force on the cat equal to zero? （d） What is the net force at time 8.5 s?

4.25 A student with mass 45 kg jumps off a high diving board. Using 6.0×1024 kg for the mass of the earth, what is the acceleration of the earth toward her as she accelerates toward the earth with an acceleration of 9.8 m/s2 ? Assume that the net force on the earth is the force of gravity she exerts on it.

4.36 An advertisement claims that a particular automobile can "stop on a dime". What net force would be necessary to stop a 850 kg automobile traveling initially at 48.0 km/h in a distance equal to the diameter of a dime, 1.8 cm?

5.80 You are designing an elevator for a hospital. The force exerted on a passenger by the floor of the elevator is not to exceed 1.64 times the passenger's weight. The elevator accelerates upward with constant acceleration for a distance of 3.6 mm and then starts to slow down. What is the maximum speed of the elevator?

5.84 If the coefficient of static friction between a table and a uniform massive rope is μs, what fraction of the rope can hang over the edge of the table without the rope sliding?

5.104 The 4.00 kg block is attached to a vertical rod by means of two strings. When the system rotates about the axis of the rod, the strings are extended as shown in the and the tension in the upper string is 82.0 N.

(a) What is the tension in the lower cord? (b) How many revolutions per minute does the system make? (c) Find the number of revolutions per minute at which the lower cord just goes slack.

5.78 High-speed motion pictures (3500frames/second) of a jumping 260 μg flea yielded the data to plot the flea's acceleration as a function of time as shown in the figure. (See "The Flying Leap of the Flea," by M. Rothschild et al. in the November 1973 Scientific American.) This flea was about 2 mm long and jumped at a nearly vertical takeoff angle. Use the measurements shown on the graph to answer the questions.

(a) Find the initial net external force on the flea. (b) How does it compare to the flea's weight? (c) Find the maximum net external force on this jumping flea. (d) When does this maximum force occur? (e) Use the graph to find the flea's maximum speed.

5.92 Block B, with mass 5.00 kg, rests on block A, with mass 8.00 kg, which in turn is on a horizontal tabletop (the figure ). There is no friction between block A and the tabletop, but the coefficient of static friction between block A and block B is 0.750. A light string attached to block A passes over a frictionless, massless pulley, and block C is suspended from the other end of the string.

What is the largest mass that block C can have so that blocks A and B still slide together when the system is released from rest?

4.10 A dockworker applies a constant horizontal force of 88.0 N to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves a distance 12.5 m in a time of 4.90

s.

You may want to review (Page) . For general problem-solving tips and strategies for this topic, you may want to view a Video Tutor Solution of Determining force from acceleration.

(a) What is the mass of the block of ice? (b) If the worker stops pushing after 4.90 s , how far does the block move in the next 5.60 s ?

5.31 A box with mass 13.0 kg moves on a ramp that is inclined at an angle of 55.0∘ above the horizontal. The coefficient of kinetic friction between the box and the ramp surface is μk =

0.300. (a) Calculate the magnitude of the acceleration of the box if you push on the box with a constant force 160.0 N that is parallel to the ramp surface and directed down the ramp, moving the box down the ramp.

(b) Calculate the magnitude of the acceleration of the box if you push on the box with a constant force 160.0 N that is parallel to the ramp surface and directed up the ramp, moving the box up the ramp.

5.47 A small model car with mass m travels at constant speed on the inside of a track that is a vertical circle with radius r = 15.0 m . The normal force exerted by the track on the car when it is at the bottom of the track (point A) is equal to 2.50mg. How much time does it take the car to complete one revolution around the track.

5.53 One problem for humans living in outer space is that they are apparently weightless. One way around this problem is to design a space station that spins about its center at a constant rate. This creates "artificial gravity" at the outside rim of the station. You may want to review (Page) . For related problemsolving tips and strategies, you may want to view a Video Tutor Solution of Force in uniform circular motion.

(a) If the diameter of the space station is 840 m , how many revolutions per minute are needed for the "artificial gravity" acceleration to be 9.80m/s2? (b) If the space station is a waiting area for travelers going to Mars, it might be desirable to simulate the acceleration due to gravity on the Martian surface (3.70m/s2). How many revolutions per minute are needed in this case?

5.61 In a repair shop a truck engine that has mass 421 kg is held in place by four light cables . Cable A is horizontal, cables B and D are vertical, and cable C makes an angle

of 37.1∘ with a vertical wall. Tension in cable A is 753 N .

(a) What is the tension in cable B? (b) What is the tension in cable C?...