90 terms

Pysical Science 1

Test 1 Phys 1415
Science is a body of knowledge that goes back to
D. Humankind's beginnings
The average speed of a horse that gallops a distance of 10 km in a time of 30 min is
B. 20 km/h
An apple weighs 1 N. The magnitude of net force on the apple when it is in free-fall is
C. 1N
If a freely falling object were somehow equipped with a speedometer on a planet where the acceleration due to gravity is 20m/s/s, then its speed reading would increase each second by
A. 20m/s
A push on a 1-kg brick accelerates the brick. Neglecting friction, to equally accelerate a 10-kg brick, one would have to push with
A. 10 times as much force
A bullet is dropped into a river from a very high bridge. At the same time, another bullet is fired from a gun, straight down towards the water. Neglecting air resistance, the acceleration just before striking the water
A. Is the same for each bullet
Hand from a pair of gym rings and the upward support forces of the rings will always
C. add up to equal your weight
When a scientist is dishonest and reports false information, he or she
A. gets no second chance in the scientific community
In Science, a theory is
A. A synthesis of a large body of well-tested knowledge
The amount of fiction that occurs when two material surfaces slide against each other depends on
C. both of these- A.how much they are pressed together and B.the "stickiness" of atoms on their surfaces
Your weight is
C. The gravitational attraction between you and the earth
A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that
B. The milk carton has inertia
When a woman stands at rest with two feet on a scale, the scale reads 500 N. When she gently lifts one foot, the scale reads
A. 500N
Disregarding air resistance, objects fall at constant
C. acceleration
A 500-N parachutist opens his chute and experiences an air resistance force of 800N. The net force on the parachutist is
D. 300N upward
If you are carrying a heavy bag of groceries and band your hand against the wall, the concept that most explains why you are hurt is
C. Inertia
Which has Zero acceleration? An object
D. all of the above- A. Moving at constant velocity B. At rest C.In mechanical equilibrium
The forces required to maintain an object at a constant velocity in free space is equal to
A. Zero
A packing falls off a truck that is moving 30m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is
B. About 30m/s
Compared with a 1kg block of solid iron, a 2kg block of solid iron has the same
E. none of these- A. Weight B. Mass C. Volume
A car accelerates from rest at 2m/s/s. What is the speed 3s after the car stars moving?
B. 6m/s
An object is pulled northward with a force of 10N and southward with a force of 15N. The magnitude of the net force on the object is
C. 5N
The resistive force of friction occurs for
C. Solids
If you push a create across a level floor at constant speed, the friction between the create and the floor is
B. a bit more than your pushing force
The scientist to first introduce the concept of inertia was
D. Galileo
A man weighing 800N stands at rest on two bathroom scale so that his weight is distributed evenly over both scales. The reading on each scale is
C. 400N
A force is a vector quantity because it has both
B. Magnitude and direction
A 10kg block is pushed across a horizontal force of 20N against a friction force of 10N. The acceleration of the block in meters per second per second is
A. 1
A ball is thrown upwards and caught when it come back down. In the presence of air resistance, the speed with which it is caught is
C. Less than the speed it had when thrown upwards
A scientific hypothesis is a(n)
E.Testable assumption used to explain and observation
An object is in free-fall. At one instant, it travels at a speed of 50m/s. Exactly 1s later, its speed is about
C. 60m/s
A truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strikes the floor
B. Exactly below the midpoint of the ceiling
Whenever the net force on an object is zero, its acceleration
B. Is Zero
If a car increases its velocity from zero to 60m/h in 10s, its acceleration is
E. 6km/h/s
Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to
B. Follow a straight-line path
A falling object that has reached its terminal speed continues to gain
D. Neither-A. Speed B. Acceleration
Suppose a particle is being accelerated through space by a 10N force. Suddenly the particle encounters a second force of 10N in the opposite direction of the first force. The particle with both forces acting on it
D. Continues at the speed it had when it encountered the second force
A 1kg mass at the earth's surface weighs about
A light woman and a heavy man jump from an airplane at the same time and open their same-size parachutes at the same time. Which person will get to a state of zero acceleration first?
B. The light woman
The gain in speed each second for a freely falling object is about
C. 10 m/s
The force of friction on a sliding object is 10N. The applied force needed to maintain a constant velocity is
C. 10N
A tow truck exerts a force of 3000N on a car, accelerating it at 2m/s/s. What is the mass of the car?
D. 1500kg
The scientific method is most effective in
D. Gaining, organizing, and applying new knowledge
The two measurements necessary for calculating average speed are
A. Distance and time
A kilogram is a measure of an objects
C. Mass
Ten seconds after starting from rest, a freely falling object will have a speed of about
B. 100m/s
Consider drops of water that leak from a dripping faucet. As the drops fall, they
B. Get farther apart
The human body can, under certain conditions, withstand an acceleration of 10g. What net force would produce this acceleration on a 50kg person?
B. About 5000 N
An object weighs 30N on Earth. A second object weighs 30N on the moon. Which has a greater mass?
B. The one on the moon
If a non rotating object has no acceleration, then we can say for certain that it is
A. In mechanical equilibrium
Neglecting friction, a large block of ice and a small block of ice start sliding down an incline together. The heavier block will get to the bottom
B. The same time as the light block
A rock is thrown vertically into the air. At the top of its path, its acceleration in meter per second per second is about
B. 10
Whereas Aristotle relied on logic in explaining nature, Galileo relied on
D. Experiment
What is the acceleration of a car that maintains a constant velocity of 100 km/h for 10s?
A. 0m/s
An object in mechanical equilibrium is an object
D. All of the above-A. at rest B. Moving with constant velocity C. Having no acceleration
An object that is propelled along a straight line path by a force. If the net force were doubled, its acceleration would
C. Double
A girl pulls on a 10kg wagon with a constant force of 30N. What is the wagon's acceleration in meters per second per second?
E. 3.0
A 10N falling object encounters 4N of air resistance. The Magnitude of the net force on the object is
D. 6N
A skydiver steps from a helicopter and falls for 5s before reaching her terminal velocity. During this 5s interval, her acceleration
D. Decreases
What is the first step in the scientific process?
A. Observe a natural phenomenon
It takes 6s for s stone to fall to the bottom of a mine shaft. How deep is the shaft?
D. About 180m
Compared with the mass of a certain object on Earth, the mass of the same object on the moon is
A. The same
The two objects of the same size, but unequal weights are dropped from a tall tower. Taking air resistance into consideration, the object to hit the ground first will be the
A. Heavier object
Starting from rest, the distance a freely falling object will fall in 10s is about
D. 500m
A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is
C. 0N
A 300kg bear grasping a vertical tree slides down at constant velocity. The friction force between the tree and the bear is
C. 3000N
An empty roller coaster car at an amusement park takes 3 min to make its ride from start to finish. Neglecting friction, a fully loaded car would take
C. 3 min
If a freely falling object were somehow equipped with an odometer to measure the distance is travels, then the amount of distance it travels each succeeding second would be
C. Greater than the second before
One-half second after starting from rest, a freely falling object will have a speed of about
B. 5m/s
Two factors that greatly affect air resistance on falling objects are the size and
A. Speed of the object
An object following a straight line path at constant speed
D. has zero acceleration
An object travels 8m in the first second of travel, 8m again during the second second of travel, and 8m again during the third second. Its acceleration in meters per second per second is
D. 0
When an object falls through the air, its velocity increases and its acceleration
A. Decreases
When a falling object has reached its terminal velocity, its acceleration is
C. Zero
Galileo's interpretation of motion differed from Aristotle's in that Galileo emphezied
A. Time rates
Compared with a 1kg block of solid iron, a 2kg block of solid iron has twice as much
D. All of these- A. Inertia B. Volume C. Mass
If the mass of an object does not change, a constant net force on the object produces constant
B. Acceleration
In each second of fall, the distance a freely falling object will fall is
A. Increasing
A force of 1N accelerates a mass of 1kg at the rate of 1m/s/s. The acceleration of a mass of 2kg acted upon by a force of 2N is
B. The same
One object that has twice as much mass as another object also has twice as much
D. Inertia
Which of the following is not a fundamental quantity?
A. weight
The mass of a cubic meter of water is
A. A metric ton
Which statement is incorrect
B. A kg is longer than a mi
Which of the following is not a standard metric unit
D. Gram
The metric prefix that means one-hundredth (1/100) is
B. Centi-.
A cubit centimeter of pure water at maximum density has a mass of
A. 1 gram
When multiplying and /or dividing quantities, you should report
D. The result rounded to the number of digits as in the quantity with the least number of significant figures
A measurement of 0.00254 gram is the same as
D. 2.54mg
Which of the following is a unit of mass density?
A. Kg/m3
In buying a product, a shopper has a choice of the following amounts, all at the same price. Which is the best buy?
C. A half liter