Physics Review PDF

A Carnot engine operates between two temperature reservoirs at 600 K and 300 K. If the engine absorbs 2,000 J of heat from the hot reservoir, what is the heat rejected to the cold reservoir? a. 1500 J b. 1200 J c. 1000 J d. 700 J In the absence of net external torque, when does the angular momentum...

A Carnot engine operates between two temperature reservoirs at 600 K and 300 K. If the engine absorbs 2,000 J of heat from the hot reservoir, what is the heat rejected to the cold reservoir? a. 1500 J b. 1200 J c. 1000 J d. 700 J In the absence of net external torque, when does the angular momentum of a system is conserved? a. Never b. At all times c. Sometimes d. When angular velocity remains unchanged In an adiabatic expansion, the volume of the gas increases. What happens to its temperature? a. It increases. b. It decreases. c. It stays constant. d. It fluctuates. The SI unit of angular momentum is expressed a. as: b. c. In a constant temperature closed system process, 120 kJ of heat is transferred to the working fluid at 38 deg C. What is the change in entropy of the working fluid in kJ/K? a. 0.386 kJ/K b. 0.458 kJ/K c. 0.587 kJ/K d. 0.679 kJ/K Which of the following correctly describes the relationships between torque and angular momentum? a.Torque is the rate of change of linear momentum. b.Torque is the rate of change of angular momentum. c.Torque and angular momentum are unrelated. d.Torque only affects linear momentum. Which of the following statements clearly states the Third Law of Thermodynamics? a. The entropy of an isolated system always increases. b. The total energy of an isolated system is constant. c. As temperature approaches absolute zero, the entropy of the system approaches a minimum constant. d. Heat cannot spontaneously flow from a colder to a hotter body. What happens to its angular momentum if you apply a torque to a door that is hinged at one end? a. It remains constant. b. It increases if the torque is in the direction of rotation. c. It decreases if the torque is in the direction of rotation. d. It only changes if the door is not moving. What is entropy? a. Entropy is the energy flow in a system. b. Entropy is a measure of disorder or randomness of a system. c. Entropy is the ability of the system to do work. d. Entropy is the average kinetic energy of particles in a closed or open system. How does a larger distance from the hinge (lever arm) affect torque? a. It decreases the torque. b. It has no effect on torque. c. It increases the torque for the same applied force. d. It makes the torque negative. It is defined as the ratio of the force of gravity on a unit volume. a.Specific weight b.Specific volume c.Mass density d.Specific entropy A force of 300 N acts perpendicularly on one end of a 2.5 m long rod which has a mass of 10 kg and is initially at rest. Compute the torque acting on the rod. a. 720 N-m b. 730 N-m c. 740 N-m d. 750 N-m Which of the following describes the heat exchange in an adiabatic process? a. Heat is absorbed by the system. b. Heat is released by the system. c. No heat is exchanged with the surroundings. d. Heat is transferred depending on the work done. What is the final angular momentum of the rod if the force acts on it for 8 seconds? a. b. c. Which law of thermodynamics explains why no process can be 100% efficient? a. First law b. Second law c. Third law d. Zeroth law What is the final angular speed of the rod? a. 288 rad/sec b. 298 rad/sec c. 308 rad/sec d. 318 rad/sec What is the effect of increasing the temperature of an ideal gas in an isochoric process? a. The volume doubles. b. The volume decreases. c. The pressure increases. d. The pressure decreases. Which of the following statements is NOT one of Kepler’s Law of Planetary Motion? a. Planets move in elliptical orbits with the Sun at one focus. b. A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. c. The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit. d. All planets have circular orbits. In an ideal gas undergoing an isothermal process, which of the following statements accurately describes a system when heat is added? a. Equal to the work done by the system. b. Greater than the work done by the system. c. Less than the work done by the system d. Equal to zero. What does Newton’s Law of Universal Gravitation state? a. The gravitational force between two masses is directly proportional to the distance between them. b. The gravitational force between two masses is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. c. The gravitational force is constant and does not change with distance. d. The gravitational force between two masses is inversely proportional to the product of their masses and directly proportional to the square of the distance between them. A closed vessel contains air at a pressure of 160 Kpag and a temperature of. The air is heated at a constant volume to with an atmospheric pressure of 759 mm Hg. What is the final gauge pressure? a. 174 kPag b. 186 kPag c. 167 kPag d. 172 kPag How does mass affect gravitational force between two objects? a. Greater mass increases the gravitational force. b. Greater mass decreases the gravitational force. c. Mass has no effect on the gravitational force. d. Gravitational force is only dependent on distance. An air bubble rises from the bottom of a well where the temperature is , to the surface where the temperature is. Find the percent increase in the volume of the bubble if the depth of the well is 5m. Atmospheric pressure is 101, 528 Pascals. a. 56.7 % b. 49.3% c. 41.3% d. 38.6% Which of the following correctly describes a geostationary orbit? a. It is a low orbit that allows satellites to pass over the poles. b. It allows a satellite to remain above the point on Earth’s surface. c. It is an orbit that changes periodically. d. It is an elliptical orbit. Why is the Carnot Cycle considered the most efficient thermodynamic cycle? a. The Carnot Cycle can both receive and reject energy at the upper and lower temperatures. b. The Carnot Cycle has the ability to operate at higher compression ratios. c. The Carnot Cycle can both receive and reject energy at the upper temperature range d. The Carnot Cycle is excellent by converting high heat of vaporization of the working fluid into mechanical energy According to Kepler’s third law, if a planet’s orbital period increases, what happens to its distance from the Sun? a. It decreases. b. It remains the same. c. It increases. d. It varies randomly. A pressure of 35 kPa is measured 4 m below the surface of an unknown liquid. What is the specific gravity of the liquid? a. 0.09 b. 0.89 c. 0.93 d. 1.85 If the radius of a circular orbit is doubled, how does the orbital velocity change? a. It doubles. b. It halves. c. It increases by a factor of square root of 2. d. It decreases by a factor of square root of 2. How high does a mercury barometer stand on a day when atmospheric pressure is 98.6 kPa considering that the specific gravity of mercury is 13.6? a. 739 mm b. 760 mm c. 724 mm d. 762 mm If the spring constant (k) of a mass-spring system increases, what happens to the frequency? a. It decreases. b. It remains the same. c. It increases. d. It fluctuates. A hydraulic lift is to be used to lift a truck weighing 5000 lb. What is the pressure (gage) that must be applied to oil if the diameter of the larger piston is 12 inches? a. 17.6 psi b. 24.5 psi c. 42.7 psi d. 44.2 psi The type of energy does a mass-spring system have at the equilibrium position. a. Kinetic energy only b. Elastic potential energy only c. Both kinetic and elastic potential energy d. No energy Convert a vacuum pressure of 110 mm of mercury into absolute pressure if the atmospheric pressure is 10.5 meters of water. a. 76.0 kPa b. 82.7 kPa c. 88.3 kPa d. 94.2 kPa What is the total mechanical energy in a mass- spring system is? a. Always increasing. b. Always constant. c. Always decreasing. d. Randomly varying. If an object weighs 100 N in air and 80 N in water, what is the buoyant force acting on the object? a. 20 N b. 60 N c. 90 N d. 120N In a simple harmonic motion, if the amplitude is increased, what happens to the energy of the system? a. It fluctuates randomly. b. It remains constant. c. It decreases. d. It increases. If a hydraulic press has a smaller piston area of 0.01 m^2 and a larger piston area of 0.2 m^2, how much force must be applied to the small piston to lift a 500 N load? a. 100 N b. 75 N c. 50 N d. 25 N In a mass-spring system, what is the elastic potential energy at maximum displacement? a. Zero b. Minimum c. Maximum d. Constant In an open tank, what happens to the water level when an object is submerged? a. It stays the same. b. It increases. c. It decreases. d. It fluctuates. Which of the following statements describes the relationship between elastic potential energy and kinetic energy in a simple harmonic motion? a. There is no relationship. b. Elastic potential energy is always greater than kinetic energy. c. Elastic potential energy and kinetic energy are equal at all points. d. Elastic potential energy and kinetic energy interchange as the object moves. In a venturi meter, what happens to fluid velocity as the cross-sectional area decreases? a. It decreases. b. It remains the same. c. It increases. d. It fluctuates. Which of the following correctly describes the Doppler effect? a. Change in frequency due to the motion of the source or observer. b. Change in amplitude due to distance from the source. c. Reflection of waves off a surface. d. Refraction of waves as they enter a new medium. 1.How much heat is required to raise the temperature of 5 lb of water from 77 deg F to 167 deg F? (Specific heat capacity of water = ) a. 464.75 kJ b. 474.75 kJ c. 484.75 kJ d. 494.75 kJ In the context of sound intensity, which of the following correctly describes the inverse square law? a. Intensity is proportional to the square of the distance. b. Intensity decreases as the square of the distance from the source increases. c. Intensity is constant regardless of the distance. d. Intensity increases with distance from the source. Which of the following statements best describes Thermal equilibrium implies? a. No heat transfer occurs between two bodies. b. One body is always hotter than the other. c. Both bodies are at different temperatures. d. Bodies can still exchange energy. What type of wave requires a medium to propagate? a. Electromagnetic wave b. Radio wave c. Light wave d. Mechanical wave Which of the following principles explains why airplanes can fly? a. Newton’s Third Law b. Archimedes’ Principle c. Pascal’s Law d. Bernoulli’s Principle What is the particle motion in a transverse wave? a. Parallel to the direction of wave travel. b. Perpendicular to the direction of the wave travel. c. Random and chaotic. d. Circular. If the pressure at the sea bed is 2,032.56 Kpag, what is the depth in km of the ocean assuming SG = 1.03? a. 0.603 km b. 0.804 km c. 0.201 km d. 0.402 km If the distance from the sound source is doubled, what would be the intensity of the sound? a. Halved. b. Doubled. c. Quartered. d. Tripled.