Physics 131 (Test 1)
How many millimeters are there in one meter?
10^3
Vector A , which is shown in the figure, has a magnitude of 10 and a direction angle of 60º. What is the magnitude and direction angle (as measured counterclockwise from the positive x-axis) of −A /2?
5, 240º
Vector A has a magnitude of 2.00 m and vectorB has a magnitude of 5.00 m. If the direction of each vector is unknown, what is the largest possible value for the magnitude of A-B?
7.00 m
In the study of physics, what distinguishes a scalar from a vector?
A scalar is specified with a single number, but a vector is specified using both a magnitude and a direction.
A football player kicks a football in a field goal attempt. When the football reaches its maximum height, what is the relationship between the direction of the velocity and acceleration vectors? Assume air resistance is negligible.
At the maximum height, the velocity and acceleration vectors are perpendicular to each other.
Which of the following best describes how to calculate the average acceleration of any object?
Average acceleration is always equal to the change in velocity of an object divided by the time interval.
Which of the following is a vector? Distance Temperature Displacement Mass Speed
Displacement
What does it look like when a motorcycle has speed increasing on a velocity versus time graph?
Linear negative slope in first quadrant
The same net force is applied to two different objects. The second object has twice the mass of the first object. Compare the acceleration of the two objects.
The acceleration of object 1 is twice the acceleration of object 2.
The figure shows the velocity versus time graph for a car driving on a straight road. Which of the following best describes the acceleration of the car? * Figure is half parabola going up in positive direction
The acceleration of the car is positive and decreasing.
A car traveling due east at 20 m/s reverses its direction over a period of 10 seconds so that it is now traveling due west at 20 m/s. What is the direction of the car's average acceleration over this period?
The car's average acceleration points due west.
A large truck collides head-on with a small car. The car is severely damaged as a result of the collision. According to Newton's third law, how do the forces acting between the truck and car compare during the collision?
The force on the truck is equal to the force on the car.
For general projectile motion, which of the following best describes the horizontal component of a projectile's acceleration? Assume air resistance is negligible.
The horizontal component of a projectile's acceleration is zero.
For general projectile motion, which of the following best describes the horizontal component of a projectile's velocity? Assume air resistance is negligible.
The horizontal component of a projectile's velocity remains a nonzero constant.
An object is moving with constant velocity. Which of the following best describes the force(s) acting on the object?
The net force acting on the object is zero.
A constant net force acts on an object. Which of the following best describes the object's motion?
The object is moving with a constant acceleration.
An object is moving in the absence of a net force. Which of the following best describes the object's motion?
The object will continue to move with a constant velocity.
A pilot releases a package from a plane flying horizontally at a constant speed. When the package reaches the ground below, what is the horizontal location of the plane with respect to the package? Assume air resistance is negligible.
The plane will be located directly above the package.
Suppose that you toss a rock upward so that it rises and then falls back to the earth. If the acceleration due to gravity is 9.8 m/sec2, what is the rock's acceleration at the instant that it reaches the top of its trajectory (where its velocity is momentarily zero)? Assume that air resistance is negligible
The rock has a downward acceleration of 9.8 m/s^2
A red water balloon is thrown horizontally from the top of a bridge. At the same instant, a yellow water balloon is dropped off the bridge from the same height. Compare the time of fall for the two balloons. Assume air resistance is negligible.
The two balloons hit the ground at the same time.
For general projectile motion, which of the following best describes the vertical component of a projectile's acceleration? Assume air resistance is negligible.
The vertical component of a projectile's acceleration remains a nonzero constant.
The SI base unit for mass is the
kilogram
In the equation z=ct+d, z is measured in meters and t is measured in seconds. What are the dimensions (units) of d? What are the dimensions (units) of c?
m m/s
An object is at rest on a tabletop. Earth pulls downward on this object with a force equal in magnitude to mg. If this force serves as the action force, what is the reaction force in the action-reaction pair?
the object pulling upward on Earth
