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0 of 30. The SI units of mass are:. Kilograms Pounds g/cm 3 Grams. 0 of 30. The pull of earth’s gravity on an object equals_____. Mass in kilograms times 9.8 m/s 2 Mass times the acceleration of the object 9.8 N Density times volume. 0 of 30.
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0 of 30 The SI units of mass are: • Kilograms • Pounds • g/cm3 • Grams
0 of 30 The pull of earth’s gravity on an object equals_____. • Mass in kilograms times 9.8 m/s2 • Mass times the acceleration of the object • 9.8 N • Density times volume
0 of 30 The kinetic energy of an object is equal to: • mv • F/A • W/t • ½ mv2 • Fd
0 of 30 Which of the following is NOT measured in Joules? • Work • Kinetic Energy • Potential Energy • Heat • Power
0 of 30 The rate at which work is done is: • Power • Momentum • Kinetic Energy • Efficiency
A TV set is pushed a distance of 2 m with a force of 20 N acting in the direction of motion. How much work did the force do on the TV? • 2 J • 10 J • 20 J • 40 J • 80 J 0 of 30
Which requires more work: lifting a 50 kg object 2 meters, or lifting a 25 kg object 4 meters? • The 50 kg object • The 25 kg object • Both require the same work 0 of 30
A 2 kg mass has 40 J of potential energy relative to the ground. How far is it above the ground? • 1 meter • 2 meters • 3 meters • 4 meters • None of these 0 of 30
The kinetic energy of a moving object increases from 5.0 J to 12 J. How much work was done on the object? • None • 17 J • 60 J • 7 J • 2.4 J 0 of 30
If the speed of an object doubles its kinetic energy: • Is cut in half • Quadruples • Doubles • Does not change 0 of 30
A 50 N force acts north on an object that moves 4.0 meters east. The work done by the force is: • 200 J • 12. 5 J • 0.0 J • 54 J 0 of 30
A 50 kg skier is moving at 8.0 m/s when they are still 12 meter above the bottom of the hill. Which of the following is true? • KE = 1.6 kJ • PE = 6.0 kJ • Etotal=7.6 kJ • All of the above 0 of 30
A 50 kg skier is moving at 8.0 m/s when they are still 12 meter above the bottom of the hill. If friction and air resistance can be ignored, their kinetic energy at the bottom will be: • 1.6 kJ • 6.0 kJ • 7.6 kJ • None of the above 0 of 30
A diver who weighs 500 N steps of a diving board that is 10 meters above the water. The diver hits the water with a kinetic energy of: • 10 J • 500 J • 510 J • 5 kJ • > 5 kJ 0 of 30
Which has greater kinetic energy, a car traveling at 30 km/hr or one half as massive traveling at 60 km/hr? • The 30 km/hr car • The 60 km/hr car • Both have the same kinetic energy 0 of 30
0 of 30 To do 35 J of work in 5.0 seconds requires a power of: • 7.0 Watts • 30 Watts • 175 Watts • 40 Watts
The energy stored in an ideal spring is given by: • U=mgh • U=kx • U=kx2 • U=kx2/2 0 of 30
0 of 30 The work done by a force acting parallel to the displacement equals: • Fd • F/d • d/F • F-d
0 of 30 The work done by a machine divided by the amount of work required to operate it describes ____. • Efficiency • Percent error • Mechanical Advantage • Power
0 of 30 The energy used by a 100 W light bulb in 4 seconds is: • 25 J • 400 J • 96 J • 0.04 J
Hooke’s Law: • |F| = |kx| • |F| = |k/x| • |F| = |x/k| • |k| = |Fx| 0 of 30
0 of 30 A 3.0 kg object is moving at 4.0 m/s. Its kinetic energy is: • 12 J • 48 J • 24 J • 1.33 J
0 of 30 A 4.0 kg object is lifted upward by 2.0 meters. The increase in its gravitational potential energy is: • 2.0 J • 8.0 J • 80 J • 0.2 J
In a hydraulic system piston A has a larger area than piston B. Which of the following best describes the relationships of the pressure and force on the two pistons? • PA>PB, FA=FB • PA<PB, FA>FB • PA=PB, FA>FB • PA=PB, FA<FB 0 of 30
By applying a pressure over a larger surface hydraulic systems can multiply a force. • True • False 0 of 30
By applying a pressure over a larger area hydraulic lifts reduce the amount work required to lift a car. • True • False 0 of 30
Much like simple machines, hydraulic systems can reduce the force you need to exert but require you to exert that force over a longer distance. • True • False 0 of 30
A1=50 cm2 A2=450 cm2F1=750 N P1=? P2=? • P1=15 Pa P2=135 Pa • P1=150 kPa P2=150 kPa • P1=135 kPa P2=15 kPa • P1=37.5 kPa P2=337.5 kPa 0 of 30
A1=50 cm2 A2=450 cm2F1=750 N F2=? • 6.75 kN • 750 N • 15 N • 375 N 0 of 30
0 of 30 A rock hangs from a spring scale. The scale reads 5.0 N when the rock is in the air, and 3.0 N when it is submerged in water. What is the buoyant force acting on the rock? • 5.0 N • 3.0 N • 2.0 N • 8.0 N • None of these
0 of 30 An object that is partly or entirely immersed in a liquid is buoyed up by a force that is: • Equal to its own weight • Equal to the weight of the fluid it displaces. • Equal to the density of the fluid it is in. • Equal to the volume of the fluid it is in.
0 of 30 A block of styrofoam floats on a lake while a block of lead with equal volume lies submerged at the bottom of the lake. The buoyant force is greatest on the: • Styrofoam • Lead • Is the same for both
0 of 30 Compared to an empty ship, the same ship loaded with styrofoam will float: • Higher in the water • Lower in the water • At the same level in the water.
0 of 30 Water pressure is greatest against the _____ • Top of a submerged object • Bottom of a submerged object • Sides of a submerged object • None of these
0 of 30 What is the buoyant force acting on a 34,000 N ship that is floating in the ocean? • Less than 34,000 N • 34,000 N • More than 34,000 N • Depends on the density of the sea water
0 of 30 What is the weight of water which is displaced by a floating 34,000 N ship? • Less than 34,000 N • 34,000 N • More than 34,000 N • Depends on the ship’s shape • Depends on the density of the seawater
0 of 30 A completely submerged object always displaces an amount of fluid equal to its own: • Volume • Weight • Density • Mass
0 of 30 The lowest possible temperature is: • Zero degrees Celsius • -273 degrees Celsius • 4 Kelvins • -273 Kelvins
0 of 30 The force per unit area exerted on a surface is: • Density • Power • Buoyancy • Pressure • Specific Heat
0 of 30 The first law of thermodynamics states that: • The internal energy of a system can be increased by doing work or adding heat. • The bouyant force equals the weight of fluid displaced. • The entropy of the universe is always increasing.
0 of 30 Systems that are left alone tend to move toward a state of: • Greater entropy • Less entropy • No entropy
0 of 30 One hundred Joules of heat is added to a system that performs 60 Joules of work. The internal energy change of the system is: • 0 J • 40 J • 60 J • 100 J • None of these
0 of 30 The amount of mass per unit volume describes: • Pressure • Density • Power • Weight • Heat
0 of 30 If a loaf of bread is compressed, its _____ • Mass decreases • Volume increases • Density increases • None of these
0 of 30 One kilogram of styrofoam has _____ density than one kilogram of iron • A smaller • A greater • The same
0 of 30 Which has the greater density, a lake full of water or a cup full of lake water? • The cup full of lake water • The lake • Both have the same density
0 of 30 A wooden block has a mass of 800 g and a volume of 2 cm3. What is the block’s density? • 800 g/cm3 • 400 g/cm3 • 1600 g/cm3 • 0.4 g/cm3 • 0.025 cm3/g
0 of 30 If the mass of an object doubled while its volume remained the same its density would: • Halve • Double • Stay the same
0 of 30 When you touch a cold piece of ice with your finger • Energy is transferred from your finger to the ice • Cold is transferred from the ice to your finger • The total energy of the system increases