Honors Physics Mid-Term

In a coordinate system, the x-component of a given vector is equal to that vector's magnitude multiplied by which trigonometric function, with respect to the angle between the vector and the x-axis? a. the cosine of theta b. the sine of theta c. the tangent of theta d. the cotangent of theta e. the arc of cosine theta

A. the cosine of theta

Which of the following is NOT an example of projectile motion? a. A volleyball served over a net b. A baseball hit by a bat c. A hot-air balloon drifting toward earth d. A long jumper in action

C. a hot-air balloon drifting toward earth

A ball is thrown vertically upward from the surface of the earth. Consider the following quantities: 1. the speed of the ball; 2. the velocity of the ball; 3. the acceleration of the ball. which of these is (are) zero when the ball has reached the maximum height? a. 1 and 2 only b 1 and 3 only c. 1 only d. 2 only e. 1,2, and 3

a. 1 and 2 only

which of the following statements must be true if the expression x = v0f + 1/2at^2 is to be used? a. a is constant b. x is constant c. v is constant d. t is constant e. both v0 and t are constant

a. a is constant

if a net force of zero is acting on an object, the object is _________ a. moving at a constant velocity b. accelerating c. decelerating d. moving in a circle

a. moving at a constant velocity

with one exception, each of the following units can be used to express mass. What is the exception? a. newton b. gram c. N-sec^2/m d. kilogram e. miligram

a. newton

what does the above graph (can't find the graph but it's basically just a linear model) illustrate about acceleration? a. the acceleration is constant b. the acceleration is zero c. the acceleration decreases d. there is not enough information to answer

a. the acceleration is constant

A rock is thrown straight up from the earth's surface. Which one of the following statements concerning the net force acting on the rock at the top of its path is true? a. the net force is equal to the weight of the rock b. the net force is instantaneously equal to zero newtons c. the direction of the net force changes from up to down d. the net force is greater than the weight of the rock e. the net force is less than the weight of the rock, but greater than zero newtons

a. the net force is equal to the weight of the rock

When velocity is positive and acceleration is negative, what happens to the object's motion? a. the object slows down b. the object speeds up c. nothing happens to the object d. the object remains at rest

a. the object slows down

The drawing shows projectile motion at three points along the trajectory. the speeds at the points are v1, v2, and v3. Assume there is no air resistance and rank the speeds, largest to smallest. a. v1>v3>v2 b. v1>v2>v3 c. v2>v3>v1 d. v2>v1>v3 e.v3>v2>v1

a. v1>v3.v2

In which one of the following situations does the car have a westward acceleration? a.The car travels westward at constant speed b. the car travels eastward and slows down c.the car starts from rest and moves east d. the car travels eastward and speeds up e. the car travels westward and slows down

b the car travels eastward and slows down

For which one of the following situations will the path length equal the magnitude of the displacement? a. a jogger is running around a circular path b. A ball is rolling down an inclined plane c. A train travels 5 miles east, and then it stops and travels 2 miles west d. a ball rises and falls after being thrown straight up from the earth's surface e. A ball on the end of a string is moving in a vertical circle

b. A ball is rolling down an inclined plane

Two Objects A and B accelerate from rest with the same constant acceleration. However, object A accelerates for twice as much time as object B. Which of the following statements is true concerning these objects at the end of their respective periods of acceleration? a. Object A will travel twice as far as object B b. Object A will travel four times as far as object B c. Object A will travel eight times as far as object B d. Object A will be moving 4 times faster than object B e. Object A will be moving 8 times faster than object B

b. Object A will travel four times as far as object B

Which one of the following is not a vector quantity? a. acceleration b. average speed c. displacement d. average velocity e. instantaneous velocity

b. average speed

Two cars both start from rest and have the same constant acceleration. When radar is used to measure the velocity of each car, car A is found to be moving twice as fast as car B. At the instant the radar is used, car A has a displacement that is _____________ times as great as the displacement of car B. a. Two b. Four c. Eight d. The cars have the same displacement

b. four

A rock is thrown vertically upward from the surface of the earth. The rock rises to some maximum height and falls back toward the surface of the earth. Which one of the following statements concerning this situation is true if air resistance is neglected? a. As the ball rises, it's acceleration vector points upward b. the ball is a freely falling body for the duration of it's flight c. the acceleration of the ball is zero when the ball is at it's highest point d. the velocity and acceleration of the ball always point in the same direction

b. the ball is a freely falling body for the duration of it's flight

Ina coordinate system, the y-component of a given vector is equal to the vector's magnitude multiplied by which trigonometric function, with respect to the angle between the vector and the y-axis? a. the cosine of theta b. the sine of theta c. the tangent of theta d. the cotangent of theta e. the arc cosine of theta

b. the cosine of theta

Two point masses m and M are separated by a distance d. If the distance between the masses is increased to 3d, how does the gravitational force between them change? a. the force will be one-third as great b. the force will be one-ninth as great c. the force will be three times as great d. the force will be nine times as great e. it is impossible to determine without knowing the numerical values of m, M, and d

b. the force will be one-ninth as great

Which statement best explains why the weight of an object of mass m is different on Mars than it is on earth? a. the mass of mars is different from that of earth b.the masses and radii of mars and earth are not the same c. the mass m is further from earth's center when it is on mars d. the constant G is different on mars e. the mass m will be different on mars

b. the masses and radii of mars and earth are not the same

A spring-loaded gun is aimed horizontally and is used to launch identical balls with different horizontal velocities. The gun is at a fixed position above the floor. The balls are fired one at a time. If the velocity of the second ball fired is twice the velocity of the first ball fired, how is the horizontal range affected? a. the range for both balls will be the same. b. the range of the second ball will be twice as large as that of the first ball c. the range of the second ball will be half as much as that of the first ball d. the range of the second ball will be four times larger than that of the first ball e. the range of the second ball will be smaller than that of the first ball by a factor of 1.3

b. the range of the second ball will be twice as large as that of the first ball

Which one of the physical quantities listed below is not correctly paired with it's SI unit and dimension? a. Velocity, m/sec, [L]/[T] b. Path length, meters, [L] c. Speed, m/sec, [L]/[T] d. Displacement, m/sec^2, [L]/[T]^2

d. Displacement, m/sec^2. [L]/[T]^2

A baseball is hit upward and travels along a parabolic arc before it strikes the ground. which one of the following statements is necessarily true? a. the acceleration of the ball decreases as the ball moves upward b. the x-component of the velocity of the ball is the same throughout the ball's flight c.the velocity of the ball is zero m/s when the ball is at the highest point in the arc d. the acceleration of the ball is zero m/s^2 when the ball is at the highest point in the arc e. the velocity of the ball is a maximum when the ball is at the highest point in the arc

b. the x-component of the velocity of the ball is the same throughout the ball's flight

the magnitude of the force of gravity on an object is __________ a. frictional force b. weight c. Inertia d. mass

b. weight

Which of the following is the tendancy of an object to maintain it's state of motion? a. acceleration b. force c. velocity d. inertia e. displacement

d. Inertia

Which one of the following situations is not possible? a. a body has zero velocity and non-zero acceleration b. a body travels with a northward velocity and a northward acceleration c. a body travels with a constant velocity and a time-varying acceleration d.a body travels with a northward velocity and a southward acceleration e. A body travels with a constant acceleration and a time-varying velocity

c. a body travels with a constant velocity and a time-varying acceleration

Two balls are thrown from the top of a building. Ball 1 is thrown straight down, and ball 2 is thrown with the same velocity, but upward at an angle theta with respect to the horizontal. After the balls are released, what can you say about their accelerations? a. the acceleration of ball 1 becomes larger and larger as it falls, because the ball is going faster and faster. b. the acceleration of ball 2 decreases as it rises, becomes zero at the top of the trajectory, and then increases as the ball begins to fall towards the ground c. both balls have the same acceleration at all times d. ball 2 has an acceleration in both the horizontal and vertical direction, but ball 1 has only acceleration in the vertical direction

c. both balls have the same acceleration at all times

ball 1 is thrown into the air and it follows the trajectory for projectile motion shown in the drawing (couldn't find the drawing). at the instant that ball 1 is at the top of its trajectory, ball 2 is dropped from rest from the same height. which ball reaches the ground first? a. ball 1 reaches the ground 1st since it is moving at the top of the trajectory, while ball 2 is dropped from rest b. ball 2 reaches the ground first because it has the shorter distance to travel c. both balls reach the ground at the same time d. there is not enough information to tell which ball reaches the ground first

c. both balls reach the ground at the same time

which one of the following statements concerning the two gravitational constants, G, the gravitational constant, and g, the magnitude of acceleration due to gravity is true? a. the values of g and G depend on location b. the values of g and G do not depend on location c. the value of G is the same everywhere in the universe, but g is not d. the value of g is the same everywhere in the universe but G is not e. the values of g and G are equal on the surface of any planet, but in general, vary with location in the universe

c. the value of G is the same everywhere in the universe, but g is not

Two forces act on a hockey puck. For which orientation of the forces will the puck acquire an acceleration with the largest magnitude?

c. two straight lines pointing to the right

Each drawing shows three points of a projectile, one on it's way up, one at the top, and one on its way down. which drawing correctly represents the acceleration of the projectile at these three points?

d. A diagram which shows an arrow pointing up to the right at the first point, an arrow pointing to the right at the second point, and an arrow pointing down to the right at the last point

Which one of the following statements must be true if the expression x = v0t + at^2 is to be used? a. x is constant b. v is constant c. t is constant d. a is constant

d. a is constant

In addition to displacement, which of the following must be used for a more complete description of velocity? a. M b. kg c. change in x d. change in t

d. change in t

A meassure of the quantity of matter is _________ a. density b. weight c. force d. mass

d. mass

(There is a diagram of a ball being thrown but I can't put images in here) Which statement is true concerning the ball when it is at C, the highest point in it's trajectory? a. the ball's y-velocity and acceleration are both zero b. the ball's y-velocity is perpendicular to it's acceleration c. the ball's y-velocity is not zero, but it's acceleration is zero d. the ball's y-velocity is zero, but its acceleration is not zero e. the horizontal and vertical components of the ball's velocity are equal

d. the ball's y-velocity is zero, but it's acceleration is not zero

An object moving along a straight line is decelerating at a constant rate. Which of the following statements concerning the object's acceleration is true? a. the value of the acceleration is positive b. the direction of the acceleration is in the same direction as the displacement c. the object that is accelerating has a constant velocity d. the direction of the acceleration is in the direction opposite to that of the velocity e. The acceleration changes as the object moves along the line

d. the direction of the acceleration is opposite to that of the velocity

(There is a diagram here but I can't put images here) At which point is the y-velocity vector changing most rapidly with time? a. A b. B c. C d. D e. it is changing at the same rate at all four points

e. it is changing at the same rate at all four points

Two identical blocks are pulled along a rough surface as suggested in the figure. which one of the following statements is false? a. the coefficient of kinetic friction is the same in each case b. a force of the same magnitude is needed to keep each block moving c. a force of the same magnitude is required to start each block moving d. the normal force exerted on the blocks by the surface is the same for both blocks e. the magnitude of the force of kinetic friction is greater for the block on the right

e. the magnitude of the force of kinetic friction is greater for the block on the right

a 70 kg astronaut pushes to the left on a spacecraft with a force F in "gravity-free" space. This spacecraft has a total mass of 1.0 x 10^4 kg. during the push, the astronaut accelerates to the right with an acceleration of 0.36m/s^2. Which one of the following statements concerning this situation is true? a.the spacecraft does not move, but the astronaut moves to the right with a constant speed b. the astronaut stops moving after he stops pushing on the spacecraft c. the force exerted on the astronaut is larger than the force exerted on the spacecraft d. the force exerted on the spacecraft is larger than the force exerted on the astronaut e. the velocity of the astronaut increases while he is pushing on the spacecraft

e. the velocity of the astronaut increases while he is pushing on the spacecraft