1) A dated box of dates, of mass 5.00 kg, is sent sliding up a frictionless ramp at an angle of  to the horizontal.
The graph gives, as a function of time t, the component vx of the box’s velocity along an x axis that extends
directly up the ramp. What is the magnitude of the normal force on the box from the ramp?

2) Two blocks are in contact on a frictionless table. A horizontal force is applied to the larger block, as shown in
the figure. (a) If m1 = 2.30 kg, m2 = 1.20 kg, and F = 3.20 N, find the magnitude of the force between the two
blocks. (b) Show that if a force of the same magnitude F is applied to the smaller block but in the opposite
direction, the magnitude of the force between the blocks is 2.10 N, which is not the same value calculated in (a).
(c) Explain the difference.

3) The figure shows a box of dirty money (mass m1 = 3.00 kg) on a frictionless plane inclined at angle 1 =
30.0°. The box is connected via a cord of negligible mass to a box of laundered money (mass m2 = 2.00 kg) on a
frictionless plane inclined at angle 2 = 60.0°. The pulley is frictionless and has negligible mass. What is the
tension in the cord?

4) The figure shows an initially stationary block of mass m on a floor. A force of magnitude 0.500mg is then
applied at upward angle  = 20.0°. What is the magnitude of the acceleration of the block across the floor if the
friction coefficients are (a) μs = 0.600 and μk = 0.500 and (b) μs = 0.400 and μk = 0.300?

5) Block B in the figure weighs 711 N. The coefficient of static friction between block and table is 0.250; angle
 is 30.0°; assume that the cord between B and the knot is horizontal. Find the maximum weight of block A for
which the system will be stationary.

6) Body A in the figure weighs 102 N, and body B weighs 32.0 N. The coefficients of friction between A and
the incline are μs = 0.560 and μk = 0.250. Angle  is 40.0°. Let the positive direction of an x axis be up the
incline. In unit-vector notation, what is the acceleration of A if A is initially (a) at rest, (b) moving up the
incline, and (c) moving down the incline?

7) Suppose the coefficient of static friction between the road and the tires on a car is 0.600 and the car has no
negative lift. What speed will put the car on the verge of sliding as it rounds a level curve of 30.5 m radius?
8) A student of weight 667 N rides a steadily rotating Ferris wheel (the student sits upright). At the highest
point, the magnitude of the normal force
F N
on the student from the seat is 556 N. (a) Does the student feel
“light” or “heavy” there? (b) What is the magnitude of
F N
at the lowest point? If the wheel’s speed is doubled,
what is the magnitude FN at the (c) highest and (d) lowest point?
9) An old streetcar rounds a flat corner of radius 9.10 m, at 16.0 km/h. What angle with the vertical will be
made by the loosely hanging hand straps?

DETAILED ASSIGNMENT

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