38. The wing of an airplane has an area of 1 m² , and its wing thickness is 0.5 m. Air flows over the top at 20 m/s and under the wing at 10 m/s. The density of air is 1.2 kg/m³ . What is the net force on the wing due to Bernoulli effect? (Gravitational acceleration g = 10 m/s² )
(A) 12 N
(B) 15 N
(C) 18 N
(D) 183 N
(E) 186 N

34. A particle of mass m = 0.10 kg and speed v0 = 5.0 m/s collides and sticks to the end of a uniform solid cylinder of mass M = 1.0 kg and radius R = 20 cm. If the cylinder is initially at rest and is pivoted about a frictionless axle through its center, what is the final angular velocity (in rad/s) of the system after the collision? (A) 2.0 (B) 4.2 (C) 6.1 (D) 8.1 (E) 10

35. A set of pulleys is used for supporting the calf (100 N). Please determine the weight of the subject in the right hand side. (A) 50 N (B) 73 N (C) 100 N (D) 141 N (E) 173 N

36. Nadal received a shot with the tennis ball (60 g) travelling horizontally at 50 m/s, and returned the shot at 60 m/s horizontally in the opposite direction in 0.02 sec, what is the average force that Nadal suffered during this stroke? (A) 22 N (B) 30N (C) 180 N (D) 330 N (E) 550 N

37. The aluminum cylinder is 0.10 m2 (cross-sectional area) and 0.35 m long. What is the force exerted on its ends if the elongation is0.20 mm? (Young’s modulus of aluminum is 7.0 × 1010 Pa) (A) 2.00 × 106 N (B) 4.00 × 106 N (C) 8.00 × 106 N (D) 4.00 × 103 N (E) 2.00 × 103 N

39. A large tank of water has a hose connected to it. The tank is sealed at the top and has compressed air between the water surface and the top. When the water height h is 3.5 m the pressure of the compressed air is 4.0 x 105 Pa. Take the atmospheric pressure to be 1.0 x105 Pa. What is the speed of the water when it flows out of the hose if h is 3.5 m? (A) 30.8 m/s (B) 28.4 m/s (C) 26.8 m/s (D) 25.5 m/s (E) 23.4 m/s

40. A stainless steel container has a surface area of 0.5 m2 and thickness of 2 cm. If the container is fully filled with 57°C hot-water and the temperature in the room is 27°C, what is the rate of energy loss through the container? (The thermal conductivity of stainless steel is 80 W/m/K) (A) 30 kW (B) 60 kW (C) 120 kW (D) 180 kW (E) 210 kW

41. A jack could lift a very heavy object like a car. It compressed air and exerts a force on a small piston of area 10 cm2 and the pressure is transmitted by an incompressible liquid to a second piston of area 30 cm2 . If we want to lift a car weighting 1300 kg, what force must be exerted in the small area piston? (A) 43.3 N (B) 424.6 N (C) 433.3 N (D) 1300.0 N (E) 4247.7 N

42. An ambulance moves at a speed of 50 km/hr, and its siren emitting sound at a frequency of 5.0x102 Hz. What frequency of sound is heard by a runner who is running at 4 m/s approaching each other in the opposite direction (the speed of sound in air is 345 m/s)? (A) 47 Hz (B) 475 Hz (C) 506 Hz (D) 527 Hz (E) 555 Hz

43. One rope is wiggled with frequency f = 2.0 Hz, amplitude A = 1.0 m, and wave speed v = 4.0 m/s. What is the mathematical description of this wave? (A) y(x,t) = cosπ (2x − t) (B) y(x,t) = cosπ (2x + t) (C) y(x,t) = cosπ (x − 2t) (D) y(x,t) = cosπ (x + 2t) (E) y(x,t) = cosπ (x − 4t)

44. There is a 1 kg gallium block and its melting point is around 30°C. What is the change of entropy when it was melted from solid to liquid at 30°C? (The fusion heat of gallium is Lf = 80.18 kJ/kg) (A) 0 (B) 0.265 kJ/K (C) 0.374 kJ/K (D) 2.673 kJ/K (E) 3.779 kJ/K