Chapter 4Objective Questions14. (solve for requested variable prior to explanation)12 (solve for requested variable prior to explanation)Conceptual Questions 6

Chapter 5Objective Questions1. (assume the maximum frictional force the truck/tires can create is the same in both instances)Conceptual Questions7 (a) 9. Also, at maximum compression, how can we compare the magnitude of the mg to the normal force. Chapter 6Objective Questions4. Conceptual Questions6. 9.

I. Can an object with a single force applied have a constant speed; can it have a constant velocity?

II. A ball is tied to a string in that car hanging freely. When the car is accelerating forward uniformly the ball hangs at a set angle. Compare the force of gravity acting on the ball to the tension on the string. Provide a justification for your assessment.

III. Four boxes are accelerated uniformly by a force F (as shown) rank the forces of interaction. A on B, B on A, B on C, C on B, C on D, D on C. You can assume size is proportional to mass and there is no friction on the surface.

IV. Use vectors as well as a=ΔV/Δt to explain that ac α v2, and physically draw two vectors near an object on a circular path.

V. Considering the Atwood machine, draw vectors showing forces acting on each block of appropriate magnitude and direction. The spool has a very small relative mass. (the two objects are connected to strings and can move up or down as the pulley rotates)

VI. If every force has an equal and opposite force, how can something accelerate when it is pushed?

VII. A heavy mass hangs on a string. A string hangs below the heavy mass. If the mass is pulled downward slowly, the top string breaks. If the mass is pulled down very quickly, the bottom string breaks. Explain

VIII. Two stars rotate around each other in circular orbits. One star is twice the mass of the second. How can we compare the gravitational force each will exert on each other? How can we compare the radii of their travel (mathematically solve for requested variable prior to explanation)?

IX. A tether-ball spins on a uniform circular path, as shown (assume the ball continues to rotate from the top point with no wrapping). How can we compare the magnitude of centripetal force, tension, and mg?

X. Two lines support a mass, holding it in place. How can we compare the tensions of the two strings, T1 and T2, if we assume the drawing is to scale?

A skydiver moving at speed v, changes shape with the purpose of diving downward at a faster rate. If you were looking up at the skydiver they would look (¼) as large in the sky after changing their shape. If FD= ((Cd Aρ)/2) * V2 , where Cd is the coefficient of drag, A is the cross sectional area of the falling object, and ρ is the density of air, what should happen to the terminal velocity of this person?

Draw free body diagrams for the object indicated in each of the following examples. Make sure all force vectors have appropriate magnitude and direction. Make sure the start of each vector represents the location of origin of that force.

d. Friction exists between the boxes shown. The boxes have a mass of A and B. A is not sliding on B. The bottom surface is frictionless. Label all vectors in terms of variables a (acceleration), v (velocity), A (mass), B (mass), and g (acceleration of gravity).

e. Draw the forces acting on the car.

At minimum speed to maintain circular path

At maximum speed still maintaining circular path

f. Here, show the direction of the net force considering the path outlined.

g. Assume the pendulum is in motion on left and at the top of motion on the right. Give the direction of acceleration in each instance.