1. 
A block of mass m is accelerated across a rough surface by a force of magnitude F that is exerted at an angle φ with the horizontal, as shown above. The frictional force on the block exerted by the surface has magnitude f. What is the acceleration of the block?
o 
o 
o 
· 
o 
2. A block of mass m is accelerated across a rough surface by a force of magnitude F that is exerted at an angle φ with the horizontal, as shown above. The frictional force on the block exerted by the surface has magnitude f. What is coefficient of friction between the block and surface
o 
o 
o 
o 
· 
3. A section of hollow pipe and a solid cylinder have the same radius, mass, and length. They both rotate about their long central axes with the same angular speed. Which object has the higher rotational kinetic energy?
· the hollow pipe
o the solid cylinder
o they have the same rotational kinetic energy
o impossible to determine.
4. Two spheres roll down an incline, starting from rest. Sphere A has the same mass and radius as sphere B, but sphere A is solid while sphere B is hollow. Which arrives at the bottom first?
· Sphere A
o Sphere B
o Both arrive
o At the same time
o Impossible to determine
5. Two solid spheres roll down an incline, starting from rest. Sphere A has twice the mass and twice the radius of sphere B. Which arrives at the bottom first?
o sphere A
o sphere B
· Both arrive at the same time.
o impossible to determine
6. When a thin uniform stick of mass M and length L is pivoted about its midpoint, its rotational inertia is ML 2/12. When pivoted about a parallel axis through one end, its rotational inertia is:
o ML 2/12
o ML 2/6
· ML 2/3
o 7 ML 2/12
o 13 ML 2/12
7. The three sections of the pipe shown above have areas A1, A2, and A3. The speeds of the fluid passing through each section of the pipe are v1, v2, and v3, respectively. The areas are related by A2 = 4 A1 = 8 A3. Assume the fluid flows horizontally. Which of the following is true of the speeds of the fluid in each section in the pipe? 
· v3 = 2 v1
o v3 = 8 v2
o v2 = Ѕ v1
o v2 = 16 v1
o v3 = 64 v2
8. Consider a graphical representation (Fig.) of simple harmonic motion as described mathematically by equation 
. When the particle is at point A on the graph, what can you say about its position and velocity? 
o The position and velocity are both positive
o The position and velocity are both negative
o The position is positive, and the velocity is zero
o The position is positive and the velocity is negative
· The position is negative, and the velocity is positive
9. For an object undergoing simple harmonic motion,
o the amplitudes are usually regarded as being large
· the acceleration is greatest when the displacement is greatest
o the acceleration is greatest when the speed is greatest
o the maximum potential energy is larger than the maximum kinetic energy
o the displacement is greatest when the speed is greatest
10. Which of the following statements is not true regarding a mass- spring system that moves with simple harmonic motion in absence of friction?
o The total energy of the system remains constant
o The energy of the system is continually transformed between kinetic and potential energy
o The total energy of the system is proportional to the square of the amplitude
· The potential energy stored in the system is greatest when the mass passes through the equilibrium position.
11. Consider three point charges located at the corners of a right triangle as shown in Figure, where q 1 = q 3 = 5.0 μC, q 2 =-2.0 μC, and a = 0.10 m. Find the resultant force exerted on q 3. 
· F3 =(-1.1 i +7.9 j)N
o F3 =(7.9 i -1.1 j)N
o F3 =(1.1 i -7.9 j)N
o F3 =(1.1 i +7.9 j)N
o No correct answer
12. An electric dipole is defined as a positive charge q and a negative charge - q separated by a distance 2 a. For the dipole shown in Figure, find the electric field E at P due to the dipole, where P is a distance y» a from the origin. 
· 
o 
o 
o 
o No correct answer
13. A rod of length l has a uniform positive charge per unit length λ and a total charge Q. Calculate the electric field at a point P that is located along the long axis of the rod and a distance a from one end. 
· 
o 
o 
o 
o No correct answer
14. Calculate the ratio of the electrostatic to gravitational interaction forces between two electrons, between two protons. At what value of the specific charge q/m of a particle would these forces become equal (in their absolute values) in the case of interaction of identical particles? (γ=6.67·10-11 m3/(kg·s2), me=9·10-31kg, mp=1·10-27kg, ke=8.99·109 N·m2/ C2)
· 4·1042 (for electrons); 1·1036 (for proton); q/m=0.86·10-10 C/kg
o 4·1042 (for proton); 1·1036 (for electrons); q/m=0.86·10-10 C/kg
o 4·1045 (for proton); 1·1038 (for electrons); q/m=0.86·10-13 C/kg
o 4·1043 (for electrons); 1·1035 (for proton); q/m=0.86·10-11 C/kg
o No correct answer
15. Two positive charges q1 and q2 are located at the points with radius vectors r1 and r2. Find a negative charge q3 and a radius vector r3 of the points at which it has to be placed for the force acting on each of the three charges to be equal to zero.
· 
o 
o 
o 
o No correct answer
16. A point charge q is located at a distance l from an infinite conducting plane. Determine the surface density of charges induced on the plane as a function of separation r from the base of the perpendicular drown to the plane from the charge.
· 
o 
o 
o 
o No correct answer
17. A thin infinitely long thread carrying a charge λ per unit length is oriented parallel to the infinite conducting plane. The distance between the thread and the plane is equal to l. Find: a) the modulus of the vector of the force acting on a unit length of the thread; b) the distribution of surface charge density σ(x) over the plane, where x is the distance from the plane perpendicular to the conducting surface and passing through the thread.
· 
, 
o 
, 
o 
, 
o 
, 
o No correct answer
18. A thin wire ring of radius R carries a charge q. Find the magnitude of the electric field strength on the axis of the ring as a function of distance l from its centre.
· 
o 
o 
o 
o No correct answer
19. Find the currents I 1, I 2, and I 3 in the circuit shown in Figure. 
· I 1=2 A, I 2=-3 A, I 3=-1 A
o I 1=-2 A, I 2=3 A, I 3=1 A
o I 1=2 A, I 2=-3 A, I 3=-5 A
o I 1=3 A, I 2=2 A, I 3=1 A
o No correct answer
20. The water (H2O) molecule has an electric dipole moment of 6.3·10-30 C·m. A sample contains 1021 water molecules, with the dipole moments all oriented in the direction of an electric field of magnitude 2.5·105 N/C. How much work is required to rotate the dipoles from this orientation (θ=0°) to one in which all the moments are perpendicular to the field (θ=90°)?
o 1.6·10-24 J
· 1.6·10-3 J
o -1.6·10-3 J
o 1.6·10-25 J
o No correct answer
21. Inside the wall of a house, an L-shaped section of hot-water pipe consists of a straight horizontal piece 28.0 cm long, an elbow, and a straight vertical piece 134 cm long (Figure). A stud and a second-story floorboard hold stationary the ends of this section of copper pipe. Find the magnitude of the displacement of the pipe elbow when the water flow is turned on, raising the temperature of the pipe from 18.0°C to 46.5°C.
o 0.136 mm
o 0.649 mm
· 0.663 mm
o 28.136 mm
o 134.649 mm
22. At 25.0 m below the surface of the sea (ρ= 1 025 kg/m3), where the temperature is 5.00°C, a diver exhales an air bubble having a volume of 1.00 cm3. If the surface temperature of the sea is 20.0°C, what is the volume of the bubble just before it breaks the surface? (P0= 1.013* 105 Pa).
· 3.67 cm3
o 3.67 m3
o 36.7 cm3
o 367 cm3
o 36.7 m3
23. An aluminum cup of mass 200 g contains 800 g of water in thermal equilibrium at 80.0°C. The combination of cup and water is cooled uniformly so that the temperature decreases by 1.50°C per minute. At what rate is energy being removed by heat? Express your answer in watts. (Specific heat of aluminium and water cal =900 J/kg . °C, cw =4186 J/kg . °C).
o 85.2 W
o 86.5 W
· 88.2 W
o 95.2 W
o 98.1 W
24. 
A sample of ideal gas is expanded to twice its original volume of 1.00 m3 in a quasi-static process for which P= αV2, α=5.00 atm/m6, as shown in Figure. How much work is done on the expanding gas? (1 atm= 1.013* 105 Pa).
o 1.18 MJ
o - 1.18 J
· - 1.18 MJ
o - 118 J
o - 118 MJ
25. 
A sample of an ideal gas is in a vertical cylinder fitted with a piston. As 5.79 kJ of energy is transferred to the gas by heat to raise its temperature, the weight on the piston is adjusted so that the state of the gas changes from point A to point B along the semicircle shown in Figure. Find the change in internal energy of the gas.
· 3.6 kJ
o 1.2 kJ
o 6 kJ
o 500 kJ
o 300 kJ
26. A multicylinder gasoline engine in an airplane, operating at 2 500 rev/min, takes in energy 7.89 * 103 J and exhausts 4.58 *103 J for each revolution of the crankshaft. How many liters of fuel does it consume in 1.00 h of operation if the heat of combustion is 4.03 * 107 J/L?
o 9.4 l/h
o 19.4 l/h
· 29.4 l/h
o 39.4 l/h
o 49.4 l/h
27. Suppose a heat engine is connected to two energy reservoirs, one a pool of molten aluminum (660°C) and the other a block of solid mercury (-38.9°C). The engine runs by freezing 1.00 g of aluminum and melting 15.0 g of mercury during each cycle. The heat of fusion of aluminum is 3.97 * 105 J/kg; the heat of fusion of mercury is 1.18* 104 J/kg. What is the efficiency of this engine?
o 25.4 %
o 35.4 %
o 45.4 %
· 55.4 %
o 65.4 %
28. A plane loop of wire consisting of a single turn of cross-sectional area 100 cm2 is perpendicular to a magnetic field that increases uniformly in magnitude from 0.5 T to 2.5 T in a time of 1.5 s. What is the resulting induced current if the coil has a total resistance of 4 Ω?
o 1 A
o 2A
· 3A
o 4A
29. A 20-turn circular coil of radius 5 cm and resistance 0.5 Ω is placed in a magnetic field directed perpendicular to the plane of the coil. The magnitude of the magnetic field varies in time according to the expression B = 0.02t + 0.05t2, where t is in s and B is in T. Calculate the induced emf in the coil at t = 6 s.
o 9.74 mV
· 97.4 mV
o 974 mV
o 9.74 V
30. A body is moving parallel to the z-axes. Its velocity is constant and equal to 12 m/s. Which vector of velocity is possible:
o 
o 
· 
o 
31. The velocity of the body is 
. What is the position vector for this body (in general form)?
o 
o 
o 
· 
32. A body moves along the y-axes. When the velocity is positive? (more than one answer can be right)
· 
o 
· 
o 
33. Velocity of a body depends on time by the following form 
. What is the unit of the coefficient [B]?
o 
o 
o 
· 
34. The SI unit of density is?
· [kg/m^3]
o [kg/cm^3]
o [g/m^3]
o [1/m^3]
35. Every action or force upon an object must have an equal and ____________ reaction.
o Measurable
o Complete
· Opposite
o Correct
36. A baseball of mass m is thrown upward with some initial speed. A gravitational force is exerted on the ball
· At all points in its motion
o At all points in its motion except at the highest point
o At no points in its motion
o Only at downward part of its direction
37. The kinetic friction will always be
o Greater than static friction
o Equal to the static friction
· Less than static friction
o Negative
38. The unit of coefficient of friction in SI system is
o Newton
o Dyne
o None of these
· No unit
39. Whenever a constant force is applied on a body then it will move with __________.
o Constant Speed
o Constant Velocity
· Constant Acceleration
o None of them
40. Power is a __________.
· Scalar Quantity
o Vector Quantity
o None of these
o Rate of force
41. The dot product of force and velocity is called __________.
o Work
· Power
o Energy
o Momentum
42. When the force and displacement are perpendicular to each other, then work is __________.
· zero
o Maximum
o None of these
o Depends on force magnitude
43. Centripetal acceleration and tangential acceleration are always __________.
o Parallel to Each other, but in opposite direction
· Perpendicular to each other
o None of these
o Parallel to Each other, but in the same direction
44. The dimensions of angular momentum are __________.
o MLT-1
o MLT-2
o ML2T-2
· ML2T-1
45. The moment of inertia of a wheel about its axle does not depend upon its:
o Diameter
o Mass
o distribution of mass
· speed of rotation
46. Two waves have the same frequency. Which wave characteristic must also be identical for both waves?
o Phase
o Amplitude
o Intensity
· Period
47. A mechanical wave generally does NOT
· move the medium from one place to another
o move through a medium
o move through solids
o disturb the medium
48. The moment of inertia of a body depends on
o the angular velocity
o the angular acceleration
· the mass distribution
o the torque acting on the body
49. A skater can spin faster by pulling in her arms closer to her body or spin slower by spreading her arms out from her body. This is due to
o Conservation of momentum
o Conservation of energy
o Newton’s third law
· Conservation of angular momentum
50. The Coulomb’s law ia an equation giving the magnitude of the electric force (sometimes called the Coulomb force) between two point charges:
· 
o 
o 
o 
o No correct answer
51. The SI units for Coulomb constant ke are:
· N·m2/C2
o N·m/C
o N·m/C2
o m2/C2
o No correct answer
52. The electric field vector E can be expressed as:
· E = F e/q
o E = F e/q2
o E = F e·q
o E = F e·q2
o No correct answer
53. Which statements are correct?
· Charges of opposite sign attract one another and charges of the same sign repel one another. Total charge in an isolated system is conserved. Charge is quantized.
o Charges of opposite sign repel one another and charges of the same sign attract one another. Total charge in an isolated system is conserved. Charge is quantized.
o Charges of opposite sign attract one another and charges of the same sign repel one another. Total charge in an isolated system is not conserved. Charge is quantized.
o Charges of opposite sign repel one another and charges of the same sign attract one another. Total charge in an isolated system is ot conserved. Charge is not quantized.
o No correct answer
54. Which statements are correct?
· Conductors are materials in which electrons move freely. Insulators are materials in which electrons do not move freely.
o Insulators are materials in which electrons move freely. Conductors are materials in which electrons do not move freely.
o Conductors are materials in which electrons don’t move freely. Insulators are materials in which electrons move freely.
o All answers are correct
o No correct answer
55. If the electric field is uniform and makes an angle θ with the normal to a surface of area A, the electric flux through the surface is:
· ΦE = EA cos θ
o ΦE = EA sin θ
o ΦE = A cos θ sin θ
o ΦE = E cos θ
o No correct answer
56. Gauss’s law says that the net electric flux ΦE through any closed gaussian surface is equal to:
· ΦE=qin/ε0
o ΦE=qin·ε0
o ΦE= ε0/qin
o ΦE=qinqout/ε0
o No correct answer
57. A conductor in electrostatic equilibrium has the following properties:
· 1. The electric field is zero everywhere inside the conductor. 2. Any net charge on the conductor resides entirely on its surface. 3. The electric field just outside the conductor is perpendicular to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is greatest where the radius of curvature of the surface is the smallest.
o 1. The electric field is zero everywhere inside the conductor. 2. Any net charge on the conductor resides partially on its surface, partially inside the conductor. 3. The electric field just outside the conductor is parallel to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is greatest where the radius of curvature of the surface is the smallest.
o 1. The electric field is non zero everywhere inside the conductor. 2. Any net charge on the conductor resides entirely on its surface. 3. The electric field just outside the conductor is perpendicular to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is greatest where the radius of curvature of the surface is the biggest.
o 1. The electric field is zero everywhere inside the conductor. 2. Any net charge on the conductor resides entirely inside the conductor. 3. The electric field just outside the conductor is perpendicular to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is smallest where the radius of curvature of the surface is the smallest.
o No correct answer
58. When a positive test charge q 0 is moved between points A and B in an electric field E, the change in the potential energy of the charge–field system is:
· 
o 
o 
o 
o No correct answer
59. The potential difference ∆ V between points A and B in an electric field E is defined as:
· 
o 
o 
o 
o No correct answer
60. The potential difference between two points A and B in a uniform electric field E, where s (d=|s|) is a vector that points from A to B and is parallel to E is:
· ∆V=- Ed
o ∆V=0
o ∆V= Ed
o ∆V=- Edsinθ
o No correct answer
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