Science Final 1
20) A 10-N falling object encounters 4 N of air resistance. The net force on the object is A) 0 N B) 4 N C) 6 N D) 10 N
A
4) In science, an educated guess is a A) hypothesis B) theory C) both of the above
A
88) A machine puts out 100 W of power for every 1000 W put into it. The efficiency of the machine is A) 10 percent B) 50 percent C) 90 percent D) 110 percent E) none of the above
A
9) one object had twice as much mass as another object, and also had twice as much A) inertia B) velocity C) gravitational acceleration D) volume E) all of the above
A
90) A woman lifts a box from the floor. She then moves with constant speed to the other side of the room, where she puts the box down. How much work does she do on the box while walking across the floor at constant speed? A) 0 J B) more than 0 J C) not enough information given
A
25) a girl pulls on a 10-kg wagon with a constant force of 30 N. What it's the wagon's acceleration in meters per second squared? A) 0.3 B) 3.0 C) 10 D) 30 E) 300
B
3) The scientific method is a method for A) making hypotheses B) gaining new knowledge C) making observations D) testing theories E) designing experiments
B
6) The impulse-momentum relationship is a direct result of A) Newton's First Law B) Newton's Second Law C) Newton's Third Law
B
61) When a falling object has reached its terminal velocity, its acceleration is A) constant B) zero C) g.
B
13) the scientific spirit is based upon A) hypothesis of well-known philosophers B) honesty and trust C) consensus in the scientific community D) experimentation
D
20) A 4-kg ball has a momentum of 12 kg X m/s. What is the ball's speed? A) 3 m/s B) 4 m/s C) 12 m/s D) 48 m/s E) none of the above
A
22) Recoil is noticeable if we throw a heavy ball while standing on roller skates. If instead we go through the motions of throwing the ball but hold onto it, our net recoil will be A) zero B) the same as before C) small, but noticeable
A
11) the weight of a 0.6 kg of salami is about A) 0.06 N B) 6.0 N C) 60 N D) 600 N
B
1) Science is a body of knowledge that go back to A) humankind's beginning B) seventh century B.C. Greece C) sixteenth century Italy D) the time of Galileo
A
11) a scientific hypothesis may turn out to be right or it may turn out to be wrong. If it is a valid hypothesis, they must be a great for proving it A) right B) wrong
B
12) The statement, "there are regions beneath Earth's crust that will always be beyond the reach of scientific investigation," is a A) fact B) speculation C) hypothesis D) scientific statement E) theory
B
2) A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is A) zero B) doubled C) quadrupled D) unchanged
B
82) A ball is thrown vertically into the air. Because of air resistance, its time coming down compared to its going up is A) less B) the same C) more
C
7) compared with a 1-kg block of solid iron, a 2-kg block of solid iron has the same A) mass B) volume C) weight D) all of the above E) none of the above
E
10) Which of the following is a scientific hypothesis A) the moon is made of cheese B) there are things we will never know about C) matter it's filled with undetectable particles D) none of the above
A
10) if you are carrying a heavy bag of groceries and bang your head against the wall, the concept that most explain why you are hurt is A) inertia B) gravity C) acceleration D) resistance E) none of the above
A
45) Two identical gliders slide together each other on an air track. One moves at 1 m/s and the other at 2 m/s. They collide and stick. The combined mass moves at A) 1/2 m/s B) 1/3 m/s C) 1/6 m/s D) 3/4 m/s E) 1.5 m/s
A
12) on the surface of Jupiter, where the acceleration due to gravity is about three times that of earth, a 100-kg rock would have a weight of about A) 1000 N B) 3000 N C) 6000 N D) 9000 N
B
15) when a loaf of bread rises, it's density A) increases B) decreases C) stays the same
B
17) an object is pulled northward with a force of 10 N and southward with a force of 15 N. The magnitude of the net force on the object is A) 0 N B) 5 N C) 10 N D) 15 N
B
19) Compared with falling on a wooden floor, a wine glass may not break when it falls to a carpeted floor because of the A) lesser impulse in stopping B) longer time to stop C) both A and B D) neither A nor B
B
85) An astronaut on another planet drops a 1-kg rock from rest. The astronaut notices that the rock falls 2 m straight down in 1 s. On this planet, how much does the rock weigh? A) 1 N B) 4 N C) 5 N D) more than 5 N
B
89) An ungloved fist will do more damage to a jaw than a gloved fist. The reason for this is that the ungloved fist A) delivers a larger impulse to the jaw B) exerts a larger force on the jaw C) has less air resistance on it D) none of the above
B
When a scientist is dishonest and reports false information, he or she A) like in so many other professions, will be excused by the scientist community B) gets no second chance in the scientific community
B
46) A 5000-kg freight car runs into a 10,000-kg freight car at rest. They couple upon collision and move with a speed of 2 m/s. What was the initial speed of the 5000-kg car? A) 4 m/s B) 5 m/s C) 6 m/s D) 8 m/s E) none of the above
C
5) a kilogram is a measure of an object's A) weight B) force C) mass D) gravity E) center of mass
C
6) a package falls off a trick that it's moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is A) zero B) less than 30 m/s but larger than zero C) about 30 m/s D) more than 30 m/s W) more information needed for an estimate
C
6) compared with a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much A) inertia B) mass C) volume D) all of the above E) none of the above
D
62) A falling object that has reached its terminal speed continues to gain A) acceleration B) speed C) both A and B D) neither A nor B
D
84) A falling skydiver of mass 100 kg experiences 500-N air resistance. The acceleration of the skydiver is A) 0.2 g B) 0.3 g C) 0.4 g D) 0.5 g E) more than 0.5 g
D
87) Strictly speaking, if any electrical device in your car is turned on, more gasoline is burned by the engine. This statement is A) totally false B) true only if the car's engine is running C) true only if the car's engine is stopped D) always true E) none of the above
D
14) density is the ratio of A) weight to volume B) mass to volume C) mass to weight D) weight to mass
B
10) compared with the mass of a certain object on earth, the mass of the same object on the moon is A) less B) more C) the same
C
22) an apple weighs 1 N. The magnitude of net force on the some when it is in free-fall is A) 0 N B) 0.1 C) 1 N D) 10 N E) none of the above
C
24) a tow truck exerts a force of 3000 N on a car, acceleration at 2 m/s squared. What is the mad of the car? A) 500 kg B) 1000 kg C) 1500 kg D) 3000 kg E none of the above
C
3) A moving object on which no forces are acting will continue to move with constant A) acceleration B) impulse C) momentum D) all of the above E) none of the above
C
18) The force on an apple hitting the ground depends upon A) the speed of the apple just before it hits B) the time of impact with the ground C) whether or not the apple bounces D) all of the above
D
18) an object it's propelled along a straight-line path in space by a force. If the mass of the object somehow becomes twice as much, its acceleration A) quadruples B) doubles C) Stays the same D) halves
D
18) which has zero acceleration A) an object at rest B) an object moving at constant velocity C) an object in mechanical equilibrium D) all of the above E) none of the above
D
1) Which of the following has the largest momentum relative to the earth? A) a tightrope walker crossing Niagara B) a pickup truck speeding along a highway C) a Mack truck parked in a parking lot D) the Science building on campus E) a dog running down the street
B
12) In which of the following locations would a chunk of gold weighing 1 N have the largest mass A) the moon B) earth C) the planet Jupiter
A
14) science, art, and religion do not contradict one another because A) all three have different domains B) if you close the right one, you can forget the other two C) if you choose religion and art, you can forget about science D) if you choose science, you can forget religion and art
A
21) An apple weighs 1 N. When held at rest above your head, the net force on the apple is A) 0 N B) 0.1 N C) 1 N D) 10 N
A
8) a hockey puck is set in motion across a frozen pound. If ice friction and air resistance area neglected, the force required to keep the pick sliding at a constant velocity A) 0 N B) equal to the weight of the pick C) the weight of the pick divided by the mass of the puck D) the mass is the puck multiplied by 10 m/s E) none of the above
A
83) A ball thrown straight upward takes 10 s to go up and return to the ground. Because of air resistance, the time taken for the ball just to go up is A) less than 5 s B) more than 5 s C) 5 s
A
9) In science, an educated guess is called A) hypothesis B) theory C) both of the above
A
9) Suppose a gun were made of a strong but very light material. Suppose also that the pellet is more massive than the gun itself. For such a weapon A) the target would be safer than the shooter B) recoil problems would be lessened C) conservation of energy would not hold D) conservation of momentum would not hold E)both conservation of energy and momentum would not hold
A
9) a truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strokes the floor below. The rock hits the floor A) exactly below the midpoint of the ceiling B) ahead of the midpoint ofc the ceiling C) behind the midpoint of ceiling D) more information needed to done this problem E) none of the above
A
21) A ball is moving at 4 m/s and has a momentum of 48 kg X m/s. What is the ball's mass? A) 4 kg B) 12 kg C) 48 kg D) 192 kg E) none of the above
B
4) The difference between impulse and impact force involves the A) distance the force acts B) times the force acts C) difference between acceleration and velocity D) mass and its effect on resisting a change in momentum
B
5) In science, facts A) are absolute B) may change C) mean very little D) are more important than theories
B
5) It is correct to say that impulse is equal to A) momentum B) the change in momentum C) the force multiplied by the distance the force acts D) all of the above E) none of the above
B
5) according to Newton's law of inertia, the result of walking around much of the day is similar to tightening the head of a hammer when it's handle hits a solid surface so that we actually a little but shorter in the A) morning B) evening C) no difference, really
B
60) Two factors that greatly affect air resistance on falling objects are the size and A) mass of the object B) weight of the object C) speed of the object
B
63) If an object falls with constant acceleration, the velocity of the object must A) be constant also B) continually change by the same amount each second C) continually change by varying amounts, depending on its speed D) continually decrease E) none of the above
B
64) A heavy object and a light object are dropped at the same time from rest in a vacuum. The heavier object reaches the ground A) sooner than the lighter object B) at the same time as the lighter object C) later than the lighter object
B
8) your weight is A) actually your mass B) the gravitational attraction between you and the earth C) a property of mechanical D) all of the above E) none of the above
B
11) a 1-kg mad at earth's surface weighs about A) 1 N B) 5 N C) 10 N D) 12 N E) none of the above
C
13) an object weighs 30 N on earth. A around object weighs 30 N on the moon. Which had the greater mass A) the one on earth B) the one on the moon C) they have the same mass D) not enough information given
C
16) which has the greatest density A) 1-kg of feathers B) 10-kg of feathers C) 1-kg of lead
C
19) A 10-N falling object encounters a 4 N air resistance. The magnitude of the net force on the object is A) 0 N B) 4 N C) 6 N D) 10 N
C
2) This course will focus on A)math B) memorizing formulas C) learning concepts D) the history of science
C
43) Consider massive gliders that slide friction-free along a horizontal air track. Glider A has a mass of 1 kg, a speed of 1 m/s, and collides with Glider B, which has a mass of 5 kg and is at rest. If they stick upon collision, their speed after collision will be A) 1/4 m/s B) 1/5 m/s C) 1/6 m/s D) 1 m/s E) none of the above
C
44) A 1-kg glider and a 2-kg glider both slide toward each other at 1 m/s on an air track. They collide and stick. The combined mass moves at A) 0 m/s B) 1/2 m/s C) 1/3 m/s D) 1/6 m/s E) 1.5 m/s
C
7) In science, a theory is A) an educated guess B) less than a fact C) a synthesis of a large body of well-tested knowledge D) unchangeable
C
7) The conservation of momentum is most closely related to A) Newton's First Law B) Newton's Second Law C) Newton's Third Law
C
7) an empty roller coaster car at a amusement park takes 3 min to make it's ride from start to finish. Neglecting friction, a fully loaded car would take A) less than 3 min B) more than 3 min C) 3 min
C
8) A cannon recoils from firing a cannonball. The speed of the cannon's recoil is small because the A) force against the cannon is smaller than against the ball B) momentum is mainly concentrated in the ball C) cannon has more mass than the ball D) momentum of the cannon is smaller
C
23) a car had a mass of 1000 kg and accelerates at 2 m/s. What is the magnitude of the force exerted on the car? A) 500 N B) 1000 N C) 1500 N D) 2000 N E) none of the above
D
6) The synthesis of a large collection of information that contains well-tested and verified hypotheses about certain aspects of the world is known as a scientific A) fact B) hypothesis C) law or principle D) theory E) none of the above
D