Physics 101 Test 1
A student releases a ball from rest on an inclined plane and measures that it travels a distance of 10.0 m in a time of 4.0 s. The average speed of the ball is
2.5 m/s
A car is moving on a highway with a speed of 60 m/s. 5 seconds later the car is moving at 10 m/s in the same direction. The magnitude of the car's acceleration is
-10 because it slowed down
A ball is thrown downward on an inclined surface from the top with a speed of 30 m/s. The ball experience an acceleration of 5 m/s2. After 2 s, its velocity will be (down on the incline is considered a negative direction):
-40 m/s
If you throw a baseball straight up, what is its velocity at the highest point it reaches
0 m/s
A freely falling object (neglecting air resistance) has its velocity
Changing linearly with Time
What is the terminal velocity?
The highest speed an object reaches because air resistance offsets gravity in the real world
Instantaneous speed is calculated by choosing a short time interval during which the speed is held constant or as nearly constant as is practicable.
True
An object undergoing free fall experiences
a constant acceleration
scientific law
a generalization based upon experiments or observation
A car goes from 0 m/s to 10 m/s in 1 second, moving along the negative x-axis. What is its acceleration?
-10 m/s^2
A centimeter is
1/100 a meter
One-inch equals
2.5 cm
A ball is thrown up in the air with an initial velocity of 40 m/s. What is the ball's velocity after 2 seconds?
20 m/s traveling upward`
A great white shark can swim with a speed of about 16 meters per second. Convert the shark's speed to miles per hour. (1 mile = 1609 meters, and 1 hour = 3600 seconds)
36 miles per hour
Acceleration is scalar or vector
Scalar
Which would hit the ground first if dropped from the same height in a vacuum—a feather or a metal bolt?
They would hit the ground at the same time.
If the acceleration is zero, the velocity is constant.
True
Slope of Velocity vs. Time
acceleration
The value for the acceleration due to gravity is ms-2
downward 9.8
During every second after an object dropped from rest. The object is in free fall and its speed,
increases by 9.8 m/s
An essential feature of a scientific theory is
the making of predictions that can be tested
Which graph shows an object moving with a constant non-zero velocity?
velocity stays the same time continues to go
What is the difference between distance and displacement?
Displacement is a vector quantity and distance is a scalar
Which of these is not important to the development of scientific explanations?
Measurement, communication, debate,
The term for the application of the basic laws of nature to produce practical devices for mankind is
Technology
aceleration formula
Velocity final - velocity initial / time
Acceleration represents the
change in velocity with respect to time
When speed and direction remain the same throughout a motion, this is called?
constant velocity
Average speed is calculated by
dividing the distance traveled by the elapsed time
During the first second after an object is dropped from rest and experiences free fall its displacement
increases by 4.9 m
After it passes the peak of the path of its motion an object thrown upward has
its velocity directed downward and its acceleration directed downward
Just after it is released, an object thrown upward has
its velocity directed upward and its acceleration directed downward
Just before it reaches the peak of the path of its motion an object thrown upward has
its velocity directed upward and its acceleration directed downward
A unit of volume in the metric system is the
liter
The basic unit of length in the metric system is the
meter
The most widely used system of measurement in the world is the
metric system
When the velocity of an object does not change, what happens to its acceleration?
nothing, it does not accelerate
A negative distance implies that an object is
on the negative side of the origin
Distance is scalar or vector?
scalar
A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the ball when caught would be
the same as the speed it had when thrown upwards
In the case of uniform accelerated motion, the graph of velocity versus time is a straight line.
true
slope of a position vs time graph
v=x/t velocity
A car starts from rest and reaches 20 m/s in 5 seconds. The average acceleration of the car is
4m/s^2
A freely falling object starts from rest. After falling for 6 seconds, it will have a speed of about
60 m/s
A ball is thrown upward in the air with an initial velocity of 40 m/s. How long does it take to reach back to the point it was thrown from? (consider gravitational acceleration is 10 m/s2)
8 s
An object accelerates at 2 m/s2. Assuming the object starts from rest, how much time does it need to accelerate to a speed of 16 m/s?
8 s
When an object falls in the physics world (no air resistance) from high in the sky, what happens?
It accelerates at a constant rate until it hits the ground
In one dimensional motion, the average speed of an object that moves from one place to another and then back to the original place has which of the following properties?
It can be positive negative or zero
Velocity is a scalar or vector?
vector