PHYS 210 Final, Fall 2008

Started on | Thursday, 4 June 2009, 03:04 PM Completed on | Thursday, 4 June 2009, 05:03 PM Time taken | 1 hour 59 mins Grade | 75 out of a maximum of 103 (73%) Page: 123 4 5 6 (Next) Show all questions on one page A pressurized cylindrical tank, 5.0 m in diameter, contains water that emerges from the pipe at point C, with a Mates velocity of 50 m/s. Point A is 10 m above point B and point C is 3 m above point B. The area of the pipe at point B is 0.07 m?, and the pipe narrows to an area of 0.04 m? at point C. Assume the water is an ideal fluid in laminar flow. The mass flow rate in the pipe is closest to: Choose one answer. » 1800 Kg/s x 2000 Kg/s y @ c. 1600 Kg/s_ x d. 1200 Kg/s x 1400 Kg/s x a © Incorrect Marks for this submission: 0/4. 13 Marks: 4 Find the change in entropy (in J/K) when 5.00 moles of an ideal gas undergo a free expansion from an initial volume of 20 cm3 toa final volume of 100 cm3. Choose one answer. Correct Marks for this submission: 4/4. a.52 x b.67 y c.208 x d.71 x e191 x sad A light ray passes through a glass medium of refraction index n=1.50 and thickness T=3.0 cm (see Figure). The Marks: 4 time needed for the light to travel the glass is (ns=nanosecond=10-9 s), (speed of light 3x1 08 mis 3 Choose one answer. a.0.159ns y b.045ns x c.0.106ns x d.0.150ns x e.030ns x Correct Marks for this submission: 4/4. 18 A 360-nm thick oil film floats on the surface of the water. The index of oil is no =1.50 and that of water is nwater Mate: =1.33. The surface of the oil is illuminated from above at normal incidence with white light. The two wavelengths of light in the range 400 nm to 800 nm that are most strongly reflected are close to (answer in nm=nanometer=10° m): (1) 412 and 700 (2) 432 and 720 (3) 450 and 740 (4) 470 and 760 (5) 490 and 780 Choose one answer. a. (3) x b. (5) x ® «(4x (2) Vv e.(1) x Incorrect Marks for this submission: 0/4 ie The compressibility k of an ideal gas is defined by : Marks: 4 k= -(dV/dP)/V where V is the volume and P is the pressure and dV/dP is the derivative. If the gas is compressed isothermally, what is k (in atm” ata pressure P=2.0 atm? Choose one answer. a.15 x b.05 ¥ c.0.25 x d.20 x e.10 x Correct Marks for this submission: 4/4. a Unpolarized light is passed through three successive Polaroid filters, each with its transmission axis at 45° to the preceding filter. What percentage of light gets through? Marks: 4 Choose one answer. a. 25% x b. 50% x c.55% x d.33% x 2.125% ¥ Correct Marks for this submission: 4/4 18 Marks: 4 A force acts on a block as undergoes a displacement given by (boldface letters are vectors) r=(5.0m) i+(3.0m)j If the force the force does +270 J of work on the block, then the force could be which of the following ? (1) (90N) j (2) (60N) i - (10N) j (3) (64N) i (4) (1), (2) and (3) (5) (1) and (3) (6) none of the above answers Choose one answer. a.(1) x b. (6) x c. (3) x d.(2) x e. (5) x ® fay Correct Marks for this submission: 4/4 19 The ends of a string are fixed such that the string is held taut (inextensible) under a tension of 150 N. The string Maks: has a length L=2.2 m and a mass m=0.21 Kg. The frequency of a standing wave with three antinodes is closest to: Choose one answer. a. 25Hz x b.50Hz x 5) c.27Hz ¥ d.125Hz x e.75Hz x Correct Marks for this submission: 4/4. 20 The water level in a reservoir is maintained at a constant level. What is the exit velocity in an outlet pipe 3.0 m Marks: 4 below the water surface? Choose one answer. Correct Marks for this submission: 4/4 a54m/s x b.3.0 ms x c.49m/s x d.24m/s x e.77ms ¥ 21 Marks: 4 An un-polarized light ray incident at 45 ° at a boundary between two media, is partially reflected and partially refracted. The upper medium has an index n1 and the lower one an index n2 . The reflected ray is completely polarized. The relation between n1 and n2, that is n2 /n1 is: Choose one answer. a050 x b10¥ c.141 x d.0.707 x 2.0.25 x Correct Marks for this submission: 4/4 és One leg of a Michelson interferometer is moved slightly, such that 150 dark fringes sweep through the field . ELS! Suppose the light has a wavelength 480 nm, how far was the mirror moved in the leg? Choose one answer. a. 0.0036 mm x © b. 0.036 mm ¥ c. 0.0072 mm x d.0.072mm x e.0.36mm x £072mm x Correct Marks for this submission: 4/4. 23 A length of organ pipe is closed at one end. If the speed of sound is 344 m/s, what length of pipe (in cm) is needed to obtain a fundamental frequency of 50 Hz? Marks: 3 Choose one answer. a.172 x b. 28 x c. 688 x © d.172 y e. 86 x Correct Marks for this submission: 3/3. 24 Marks: 4 Block A of mass 5.0 Kg and a block X (unknown mass) are attached to a rope which passes over a frictionless pulley. A force P=80 N is applied horizontally as shown in the figure below keeping the block A in contact with the rough vertical wall having a coefficient of friction m,=0.30. The mass X is set such that the block A moves with an acceleration of 1.6 m/s? . The mass of the block X is closest to ?.(g=9.8 m/s2 ) VL v 'ZA Choose one answer. © a.99Kg ¥ b.8.1Kg x c. 8.7 Kg d.75Kg e93Kg x Correct Marks for this submission: 4/4.