Vertical Speed - Physics - Past Exam Paper, Exams of Physics

Download Vertical Speed - Physics - Past Exam Paper and more Exams Physics in PDF only on Docsity! Physics 3204 August 2005Page 1 of 19 PART I Total Value: 50% Instructions: Shade the letter of the correct answer on the computer scorable answer sheet provided. 1. What is the vertical speed component of a projectile that is launched at an angle of 20.0o to the horizontal with an initial speed of 30.0 m/s? (A) 30.0 cos 20.0o (B) 30.0 sin 20.0o (C) O 30.0 sin 20.0 (D) O 30.0 cos 20.0 2. Which best represents the velocity components of a projectile at its maximum height? (A) (B) (C) (D) 3. A projectile is shot horizontally at 40.0 m/s from a cannon located on a cliff 155 m high. How many seconds is the projectile in the air? (A) 0.258 s (B) 5.62 s (C) 11.0 s (D) 31.6 s 4. A ball thrown into the air has a horizontal velocity component of 12 m/s. What is the range of the ball if it lands after 3.0 s? (A) 4.0 m (B) 36 m (C) 51 m (D) 80 m 5. An arrow is fired at 45.5 m/s from a 5.75 m high tree branch, at an angle of 60o above the horizontal. What maximum height, above the ground, will the arrow reach? (A) 32.1 m (B) 73.4 m (C) 79.1 m (D) 84.9 m Physics 3204 August 2005 Page 2 of 19 6. A ball is launched at a 60o angle to the horizontal. If, 3.0 s later, it lands 12 m from the launch site, what was the magnitude of the initial velocity? (A) 2.3 m/s (B) 4.0 m/s (C) 4.6 m/s (D) 8.0 m/s 7. What is the frictional force for a 24 kg object on a horizontal surface if :k= 0.25? (A) 6.0 N (B) 24 N (C) 59 N (D) 96 N 8. Assuming no friction, which graph best represents the horizontal displacement of a projectile,? (A) (B) (C) (D) 9. Assuming no friction, which is constant for all projectiles? (A) horizontal displacement (B) horizontal velocity (C) vertical displacement (D) vertical velocoty Physics 3204 August 2005Page 5 of 19 22. In which situation would the greatest torque be exerted on the bolt? (A) F (B) F (C) F (D) F 23. The diagram below shows a 2.0 × 103 kg truck on a 20.0 m long uniform bridge that has a mass of 8.0 × 103 kg. If the truck is 6.0 m from support A, what is the magnitude of the upward force at support B? (A) 4.6 × 103 N (B) 5.9 × 103 N (C) 4.5 × 104 N (D) 8.4 × 104 N 24. What happens to a neutral electroscope that is briefly touched with a positively charged glass rod? (A) gains electrons (B) gains protons (C) loses electrons (D) loses protons 25. What is the electrical potential difference required to increase the energy of a 0.20 C charged particle by 7.0 J? (A) 0.028 V (B) 1.4 V (C) 3.5 V (D) 35 V 26. A Van de Graaf generator creates an electric field about a metal sphere. A 3.0 :C charge, near the sphere, experiences a force of 5.4 x 10 -4 N. What is the strength of the electric field at the location of the charge? (A) 1.6 x 10-9 N/C (B) 1.8 x 10-4 N/C (C) 5.4 x 10-4 N/C (D) 1.8 x 102 N/C Physics 3204 August 2005 Page 6 of 19 X Y (A) negative negative (B) negative positive (C) positive negative (D) positive positive 27. Which diagram shows the gravitational field lines about a spherical object? (A) (B) (C) (D) 28. The diagram below shows electric field lines near two charged spheres, what type of charges are present on X and Y? 29. What is the electrostatic force between two protons separated by a distance of 1.0 × 10-6 m? (A) -9.0 × 1021 N (B) -2.3 × 10-16 N (C) +2.3 × 10-16 N (D) +9.0 × 1021 N Physics 3204 August 2005Page 7 of 19 30. Two charged objects attract each other with a force, F. By what factor would the force increase if one charge is doubled, the other charge is tripled, and the distance between their centres is reduced to one quarter its original value? (A) 6 (B) 16 (C) 24 (D) 96 31. Which graph illustrates Ohm’s Law? (A) (B) (C) (D) 32. Given the resisitivity of copper is 1.72 × 10-8 S @m, what is the resistance of a 2.00 m long copper extension cord that has a diameter of 2.00 × 10-3 m? (A) 1.72 × 10-11 S (B) 6.88 × 10-11 S (C) 1.72 × 10-5 S (D) 1.10 × 10-2 S 33. An electric clothes dryer uses a 30.0 A current for 12 minutes to dry a load of clothes. This process uses 5184 kJ of energy. What is the potential difference across the dryer? (A) 12 V (B) 14 V (C) 120 V (D) 240 V Physics 3204 August 2005 Page 10 of 19 90 90 39 38Y Sr + ?→ 205 82 Pb 43. If the stopping potential of a photoelectric cell is 5.60 V, what is the maximum kinetic energy of the photoelectrons emitted? (A) 2.90 × 10-20 J (B) 8.96 × 10-19 J (C) 5.60 × 101 J (D) 3.50 × 1019 J 44. What happens to the deBroglie wavelength of an electron if its momentum is doubled? (A) decreases by a factor of 2 (B) decreases by a factor of 4 (C) increases by a factor of 2 (D) increases by a factor of 4 45. Which property does the Compton Effect describe about photons? (A) mass (B) momentum (C) wave properties (D) speed rates 46. What is the energy of the emitted photon when an electron drops from the third energy level to the second energy level? (A) 1.51 eV (B) 1.89 eV (C) 2.27 eV (D) 4.91 eV 47. How many neutrons are in the nucleus of ? (A) 82 (B) 123 (C) 205 (D) 246 48. What is missing in the nuclear decay process below? (A) photon and alpha particle (B) photon and neutrino (C) positron and alpha particle (D) positron and neutrino Physics 3204 August 2005Page 11 of 19 49. An isotope of krypton has a half-life of 3 minutes. If a sample of this isotope produces 1000 counts per minute in a Geiger counter, how many counts per minute are produced after 15 minutes? (A) 0 (B) 15 (C) 30 (D) 60 50. What types of radiation are passing through the electric field in the diagram below? X Y Z (A) alpha beta gamma (B) alpha gamma beta (C) beta alpha gamma (D) beta gamma alpha Physics 3204 August 2005 Page 12 of 19 PART II Total Value: 50% Instructions: Complete all items in this section. Your responses must be clearly presented in a well-organized manner with proper use of units, formulae and significant figures where appropriate. Value 4% 51.(a) The diagram below represents a cannon located on a 145 m high cliff. If the cannon fires a cannonball at a 25o angle below the horizontal, with an initial velocity of 75.0 m/s, how far will the cannonball travel in the horizontal direction before it hits the ground? 3% (b) A juggler throws a ball at a 70o angle to the horizontal from a height of 1.6 m. If the room is 2.8 m high, what is the maximum velocity at which the ball can be thrown to avoid hitting the ceiling? Physics 3204 August 2005Page 15 of 19 Value 4% 52.(b) What is the magnitude and direction of the net force on Q1 in the diagram below? Q1 = +3.0 :C Q2 = + 4 :C Q3 = -5.0 :C 3% (c) For the circuit below, calculate: 25 S 15 S 15 S 65 V (i) the total resistance; (ii) the current through the 25 S resistor; Physics 3204 August 2005 Page 16 of 19 Value 3% 52.(d) A power supply is connected to a heating element in the diagram below. (i) Calculate the current flowing from the element. (ii) If a total of 5.0 × 1020 electrons pass any point in the heating element circuit in 40 s, calculate the amount of power dissipated in the circuit. 2% (e) What is the cost of operating a 20.0 A clothes dryer on a 2.20 × 102 V line for two hours if the price of electrical energy is $0.082/kW@h? Physics 3204 August 2005Page 17 of 19 Value 3% 52.(f) An electron travels in a path perpendicular to a 1.00 × 10-3 T magnetic field. If the radius of the circular path is 2.0 cm, how fast must the electron be travelling? 3% (g) An oil drop with a mass of 9.80 × 10-16 kg is suspended between two horizontal parallel charged plates. If the electric field strength is 2.0 × 104 N/C, how many electrons are on the oil drop? oil drop