PHYS 211 FNL Sample 2 1 The potential energy U x of a particle is plotted below If the particle has total energy of 10 J what is the largest value of x that the particle will reach 25 20 U x in Joules 15 10 5 0 A B C D E 0 5 10 15 20 x in meters 25 30 35 35 m 30 m 20 m 9 0 m 25 m 2 A truck with failed brakes is steered up a frictionless emergency escape ramp with an inclination of 15 degrees The truck s mass is 5000 kg and its speed at the bottom of the ramp is 126 km h 35 m s Approximately what minimum length L must the ramp have if the truck is to stop momentarily along it A B C D E 490 m 65 m 810 m 250 m 782 m Page 1 PHYS 211 FNL Sample 2 3 A force acts horizontally on an object on a level surface The net force acting on the object as a function of the object s position is shown below The object is initially moving in the xdirection Where is the object s kinetic energy the greatest A B C D E Between II and III Between I and II At I At III At II 4 A 500 g block is dropped onto a relaxed vertical spring with a spring constant k 3 N cm The block becomes attached to the spring and continues downward under the influence of gravity compressing the spring 15 cm before momentarily stopping What is the speed of the block just before it hits the spring A B C D E 3 25 m s 1 8 m s 5 8 m s 1 2 m s 13 5 m s Page 2 PHYS 211 FNL Sample 2 5 A ball is thrown horizontally at 9 80 m s from a height of 44 1 m above the ground How long is the ball in the air A B C D E 4 50 s 9 00 s 3 00 s 2 12 s 1 00 s 6 Three identical blocks are going to be launched from the bases of three frictionless ramps of the same height at the same time The speeds of the blocks are chosen so that they will just reach the top of the ramps Rank the speeds of the blocks at the time of launch block A is on ramp A etc Ramp A A B C D E Ramp B vC vA vB vA vB vC vB vA vC vC vB vA vA vB vC Page 3 Ramp C PHYS 211 FNL Sample 2 7 What are coordinates of the center of mass for the uniform plate shown in the figure below y 10 cm 20 cm 10 cm x 10 cm 20 cm 10 cm 10 cm 10 cm A B C D E xcm 10 cm ycm 0 cm xcm 0 cm ycm 0 cm xcm 5 cm ycm 0 cm xcm 1 67 cm ycm 0 cm Impossible to tell since we don t know the mass of the plate 8 A tone sung by an astronaut on planet Zeus produces a sound wave described by the equation p p0 A cos 5 24 x 1 100 t with x in m and t in seconds A B C D E The wave is moving in the negative x direction at 1320 m s The wave is moving in the positive x direction at 210 m s The wave is moving in the negative x direction at 210 m s The wave is moving in the positive x direction at 1320 m s none of the above Page 4 PHYS 211 FNL Sample 2 9 A B C D E 0 00 8 00 3 61 1 08 2 78 Page 5 PHYS 211 FNL Sample 2 10 A conservative force acts on an 8 kg object which moves along the x axis The potential energy curve associated with this force is shown below If the object has a speed of 1 5 m s at x 12 m what is the force acting on the object at this point A 2 3N i B 5 N i C 5 N i D 2 3N i E We can t tell the direction of the force without knowing which way the object is moving at x 12 m Page 6 PHYS 211 FNL Sample 2 11 A uniform narrow bar resting on a flat frictionless sheet of ice is given a fast horizontal impulse J in the positive x direction off center as shown in the figure you are looking at it from above The center of mass of the bar will then y J cm x A move in the positive x direction but the bar will not rotate B move with a component along both the x and y directions but the bar will not rotate C It s impossible to say the motion depends on the exact position at which the impulse is applied off center D remain at rest while the bar rotates E move in the positive x direction while the bar rotates 12 A 6 0 kg particle moves to the right at 4 0 m s as shown The magnitude of its angular momentum about the point O is A B C D E zero 144 kg m2 s 249 kg m2 s 288 kg m2 s 24 kg m2 s Page 7 PHYS 211 FNL Sample 2 13 The free body diagram shown below best matches which of these situations A B C D E A box is moving to the right and speeding up A box is moving to the right and slowing down A box is moving to the left and slowing down A box is moving to the left and speeding up A box is moving to the left at constant velocity Page 8 PHYS 211 FNL Sample 2 14 The capital letter H is made out of three rods of length L and mass M as shown What is its moment of inertia around an axis perpendicular to the page and through the point O The moment of inertia of a single rod rotating around its endpoint is 1 3 M L2 and around its center is 1 12 M L2 O A B C D E 5 3 M L2 5 12 M L2 7 4 M L2 3 2 M L2 1 2 M L2 15 A spring which is 0 300 m long is suspended from the ceiling a 2 00 kg mass is then attached to the spring and gradually lowered to its equilibrium position If the spring stretches to a total length of 0 400 m what is its spring constant A B C D E 245 N m 49 0 N m 196 N m 65 3 N m 3920 N m Page 9 PHYS 211 FNL Sample 2 16 A 4 0 kg block is put on top of a 5 0 kg block The coefficient of static …