General Physics Test One

An airplane takes off due west at an angle of 16.0° with the horizontal. When the airplane is at a vertical height of 400 ft, what is its displacement vector? Let east be the +x direction and +z be upwards.

(-1 390 + 400 ) ft

A 16-kg mass is placed on a 25° incline and friction keeps it from sliding. The coefficient of static friction in this case is 0.574 and the coefficient of sliding friction is 0.519. The mass is given a shove causing it to slide down the incline. Taking down the incline as positive, what is the acceleration of the mass while it is sliding?

-0.47 m/s2

A cart of weight 15.0 N is accelerated across a level surface at 0.15 m/s2. What net force acts on the wagon? (g = 9.8 m/s2)

0.23 N

A 400-N crate rests on a ramp; the maximum angle just before it slips is 15.0° with the horizontal. What is the coefficient of static friction between crate and ramp surfaces?

0.27

A 200-kg box is placed on a ramp. As one end of the ramp is raised, the box begins to move downward just as the angle of inclination reaches 18.0°. What is the coefficient of static friction between box and ramp?

0.32

A bird, accelerating from rest at a constant rate, experiences a displacement of 25 m in 12 s. What is its acceleration?

0.35 m/s2

A ball is rolled horizontally off a table with an initial speed of 0.24 m/s. A stopwatch measures the ball's trajectory time from table to the floor to be 0.36 s. What is the height of the table? (g = 9.8 m/s2 and air resistance is negligible)

0.64 m

A 650-N tightrope walker stands at the center of the rope such that each half of the rope makes an angle of 10.0° with the horizontal. What is the tension in the rope?

1 870 N

Two ropes are attached to a 50-kg object. The first rope applies a force of 35 N and the second, 55 N. If the two ropes are perpendicular to each other, what is the resultant acceleration of the object?

1.3 m/s2

A mouse starts out in a corner of a room, and runs across the floor according to the following displacements: d1: 1.2 m + 0.4 m d2: 0.2 m - 0.8 m What is the magnitude of the total displacement of the mouse's position?

1.5 m

Assume everyone in the United States consumes one soft drink in an aluminum can every two days. If there are 270 million Americans, about how many tons of aluminum need to be recycled each year if each can weighs 1/15 pound and one ton = 2 000 pounds?

1.6 million tons

A baseball is released at rest from the top of the Washington Monument. It hits the ground after falling for 5.85 s. What was the height from which the ball was dropped? (g = 9.80 m/s2 and assume air resistance is negligible)​

1.68 × 102 m

A 50.0-g ball traveling at 22.0 m/s is bounced off a brick wall and rebounds at 21.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 2.50 ms, what is the average acceleration of the ball during this time interval?

1.72E+4 m/s2

milli (m)

10 to the 3rd power

What is the distance between the two polar coordinates (2.0, 30°) and (9.0, 145°)?

10.0

pico

10^-12

femto

10^-15

The prefixes which are abbreviated f, d, and T represent which of the following?

10^-15, 10^-1, and 101^2

atto

10^-18

centi (c)

10^-2

zepto

10^-21

yocto

10^-24

micro (µ)

10^-6

nano

10^-9

The ratio T/m of the prefixes M and m has what value?

10^15

An apartment has 1 100 ft2 of floor space. What is the approximate volume of the apartment?

10^4 ft^3

An object moves at a constant velocity of 12 m/s to the southwest for an interval of 20 s. Halfway through this interval, what is the magnitude of its instantaneous velocity?

12 m/s

An object moves at a constant velocity of 12 m/s to the southwest for an interval of 30 s. Halfway through this interval, what is the magnitude of its instantaneous velocity?​

12 m/s

A 60.0-kg man jumps 1.70 m down onto a concrete walkway. His downward motion stops in 0.025 seconds. If he forgets to bend his knees, what force is transmitted to his leg bones?

13 900 N

A bridge that was 10.4 m long has been washed out by the rain several days ago. How fast must a car be going to successfully jump the stream, if we neglect air resistance? Although the road is level on both sides of the bridge, the road on the far side is 3.00 m lower than the road on this side.

13.3 m/s

A sled weighs 160 N. It is held in place on a frictionless 25.0° slope by a rope attached to a stake at the top; the rope is parallel to the slope. What is the normal force of the slope acting on the sled?

145 N

John throws a baseball from the outfield from shoulder height, at an initial velocity of 41.5 m/s at an initial angle of 40.0° with respect to the horizontal. The ball is in its trajectory for a total interval of 5.00 s before the third baseman catches it at an equal shoulder-height level. (Assume air resistance negligible.) What is the ball's horizontal displacement?​`

159 m

A ball is pushed with an initial velocity of 4.0 m/s. The ball rolls down a hill with a constant acceleration of 1.7 m/s2. The ball reaches the bottom of the hill in 7.0 s. What is the ball's velocity at the bottom of the hill?

16 m/s

A shot-putter moves his arm and the 6.00-kg shot through a distance of 1.25 m, giving the shot a velocity of 8.20 m/s from rest. Find the average force exerted on the shot during this time.

161 N

A sled weighs 325 N. It is held in place on a frictionless 30.0° slope by a rope attached to a stake at the top; the rope is parallel to the slope. Find the tension in the rope.

163 N

A water rocket, launched from the ground, rises vertically with acceleration of 25 m/s2 for 2.0 s when it runs out of "fuel." Disregarding air resistance, how high will the rocket rise?

178 m

Two blocks of masses 30.0 kg and 8.0 kg are connected together by a light string and rest on a frictionless level surface. Attached to the 8.0-kg mass is another light string, which a person uses to pull both blocks horizontally. If the two-block system accelerates at 0.60 m/s2 what is the tension in the connecting string between the blocks?

18 N

When three vectors are added graphically and form a closed triangle, the largest enclosed angle between any two of the vectors cannot be greater than

180°.

A car's initial velocity is 50.0 km/h in the direction 60.0° north of east, and its final velocity is 70.0 km/h in the direction 40.0° south of east. If the time period for this journey is 30.0 minutes, what is the magnitude of the car's average acceleration?

186 km/h/h

Sphere A has a radius of 5.00 cm, and sphere B has a radius of 8.80 cm. What is the difference in volume between the two spheres?

2 330 cm3

A bird, accelerating from rest at a constant rate, experiences a displacement of 22 m in 10 s. What is the average velocity?

2.2 m/s

A 3.0-kg bowling ball experiences a net force of 8.0 N. What will be its acceleration?

2.7 m/s2

A cue ball of weight W is falling with an acceleration downward of g/3 and speed v. What is the magnitude of the drag force on the ball at this moment?

2/3 W

A boat moves at 10.8 m/s relative to the water. If the boat is in a river where the current is 2.00 m/s, how long does it take the boat to make a complete round trip of 1 100 m upstream followed by a 1 100-m trip downstream?

211 s

A stone is thrown with an initial speed of 11.5 m/s at an angle of 50.0 above the horizontal from the top of a 30.0-m-tall building. Assume air resistance is negligible, and g = 9.8 m/s2. What is the magnitude of the vertical-velocity component of the rock as it hits the ground?

25.8 m/s

A stone is thrown with an initial speed of 11.5 m/s at an angle of 50.0 above the horizontal from the top of a 30.0-m-tall building. Assume air resistance is negligible, and g = 9.8 m/s2. What is the magnitude of the horizontal displacement of the rock?

26.1 m

A stone is thrown with an initial speed of 11.5 m/s at an angle of 50.0 above the horizontal from the top of a 30.0-m-tall building. Assume air resistance is negligible, and g = 9.8 m/s2.

26.8 m/s

A fireman, 57.6 m away from a burning building, directs a stream of water from a fire hose at an angle of 35.2° above the horizontal. If the initial speed of the stream is 42.7 m/s, at what height will the stream of water strike the building?​

27.3 m

A right triangle has sides 10 m, 5 m, and 11 m. The smallest angle of this triangle is nearest

27°

Wiley Coyote has missed the elusive road runner once again. This time, he leaves the edge of the cliff at 52.4 m/s horizontal velocity. If the canyon is 140 m deep, how far from his starting point at the edge of the cliff does the coyote land?

280 m

When a drag strip vehicle reaches a velocity of 65.0 m/s, it begins a negative acceleration by releasing a drag chute and applying its brakes. While reducing its velocity back to zero, its acceleration along a straight-line path is a constant −7.10 m/s2. What displacement does it undergo during this deceleration period?

298 m

Amanda is standing at the edge of a cliff. She throws a rock vertically upward at speed v0, while at the same time throws a second rock vertically downward at the same speed. How long after the rock thrown downward hits the ground does the rock thrown upwards hit?

2v0/g

The length and width of a standard sheet of paper is measured, and then the area is found by calculation to be 91.50 in.2. The number of significant figures in the width measurement must be at least

3

Calculate (0.83 + 0.049)(4.4 × 103), keeping only significant figures.

3 900

A boxcar of mass 125 tons at rest becomes uncoupled on a 2.0° grade. If the track is considered to be frictionless, what speed does the boxcar have after 9.0 seconds?

3.1 m/s

A European sports car dealer claims that his car will accelerate at a constant rate from rest to 100 km/h in 8.00 s. If so, what is the acceleration? (Hint: First convert speed to m/s.)​

3.47 m/s2

The information on a one-gallon paint can is that the coverage, when properly applied, is 440 ft2. One gallon is 231 in3. What is the average thickness of the paint in such an application?

3.6E-3 in

A 20.0-kg traffic light hangs midway on a cable between two poles 30.0 meters apart. If the sag in the cable is 0.40 meters, what is the tension in each side of the cable?

3.7E+3 N

A room in a house has a floor area of 110 ft2. Which of the following is most likely the approximate volume of the room?

30 m3

A rock is thrown straight up with an initial velocity of 25.0 m/s. What maximum height will the rock reach before starting to fall downward? (Take acceleration due to gravity as 9.80 m/s2.)​

31.9 m

A 7.00-kg mass is placed on a 28.0° incline and friction keeps it from sliding. The coefficient of static friction in this case is 0.574, and the coefficient of sliding friction is 0.528. What is the frictional force in this situation?

32.2 N

A surveyor stands 100 m from the base of a building, and uses a transit to determine that the angle of elevation to the building's roof is 19.0°. If the transit height is 0.80 m, what is the height of the building?

35.2 m

An automobile of mass 2 500 kg moving at 50.0 m/s is braked suddenly with a constant braking force of 8 500 N. How far does the car travel before stopping?

368 m

A 9.0-kg hanging weight is connected by a string over a pulley to a 5.0-kg block sliding on a flat table. If the coefficient of sliding friction is 0.19, find the tension in the string.

37.5 N

A trapeze artist, with swing, weighs 800 N; he is momentarily held to one side by his partner so that the swing ropes make an angle of 25.0° with the vertical. In such a condition of static equilibrium, what is the horizontal force being applied by the partner?

373 N

A quarterback takes the ball from the line of scrimmage, runs backward for 12 yards, then sideways parallel to the line of scrimmage for 18 yards. He then throws a 47-yard forward pass straight downfield perpendicular to the line of scrimmage. The receiver is tackled immediately. How far is the football displaced from its original position?

39 yards

A boat travels upstream and after one hour has gone 10 km. The boat next travels downstream and after one hour has gone 18 km. If the boat's speed relative to the water is constant, what is the speed of the current in the river?

4 km/h

Maria throws two stones from the top edge of a building with a speed of 22 m/s. She throws one straight down and the other straight up. The first one hits the street in a time t1. How much later is it before the second stone hits?

4.5 s

A stone is thrown at an angle of 30° above the horizontal from the top edge of a cliff with an initial speed of 8.0 m/s. A stop watch measures the stone's trajectory time from top of cliff to bottom to be 5.9 s. How far out from the cliff's edge does the stone travel horizontally? (g = 9.8 m/s2 and air resistance is negligible)

41 m

The acceleration due to gravity on the Moon's surface is one-sixth that on Earth. An astronaut's life support backpack weighs 250 lb on Earth. What does it weigh on the Moon?

41.7 lb

A high fountain of water is in the center of a circular pool of water. You walk the circumference of the pool and measure it to be 190 meters. You then stand at the edge of the pool and use a protractor to gauge the angle of elevation of the top of the fountain. It is 55°. How high is the fountain?

43 m

A baseball leaves the bat with a speed of 47 m/s and an angle of 45° above the horizontal. A 5.0-m-high fence is located at a horizontal distance of 137 m from the point where the ball is struck. Assuming the ball leaves the bat 1.0 m above ground level, by how much does the ball clear the fence?

49.7 m

On planet Z, the standard unit of length is the foose. Ann the Astronaut is 5.2 feet tall on Earth. She lands on planet Z and is measured to be 88 foosi tall. Her partner Rachael is 92 foosi tall. How tall is Rachael on Earth?​

5.4 feet

A mosquito flies diagonally from a corner at the floor of a rectangular room, with coordinates (0, 0, 0) to the opposite corner at the ceiling, with coordinates (5.5, 3.75, h) m at a rate of 0.8 m/s. If it takes the mosquito 11 seconds to make the direct flight, what is h?

5.8 m

A train slowly climbs a 400-m mountain track which is at an angle of 8.0° with respect to the horizontal. How much altitude does it gain?

55.7 m

A plane is moving due north, directly towards its destination. Its airspeed is 210 mph. A constant breeze is blowing from west to east at 25.0 mph. In which direction is the plane pointed?

6.79° W of N

An astronaut applies a force of 450 N to an asteroid, and it accelerates at 7.0 m/s2. What is the asteroid's mass?

64 kg

A 4 500-N weight is suspended in equilibrium by two cables. Cable 1 applies a horizontal force to the right of the object and has a tension, T1. Cable 2 applies a force upward and to the left at an angle of 37.0° to the negative x-axis and has a tension, T2. Find T2.

7.5E+3 N

A cereal box has the dimensions of 0.14 m × 0.22 m × 0.070 m. If there are 3.28 feet per meter, then what is the volume of the box in cubic feet?

7.6E-2 cubic feet

The distance to a hypothetical galaxy is estimated at about 7 × 106 light years. A light year is the distance traveled by light in one year; if the speed of light is 3 × 108 m/s, about how far is it from our galaxy to this hypothetical galaxy? (1 year = 3.15 × 107 s)

7E+22 m

On planet Q the standard unit of volume is called the guppy. Space travelers from Earth have determined that one liter = 39.0 guppies. How many guppies are in 230 liters?

8 970 guppies

A 500-N tightrope walker stands at the center of the rope. If the rope can withstand a tension of 1 800 N without breaking, what is the minimum angle the rope can make with the horizontal?

8.0

A trapeze artist, with swing, weighs 700 N; he is being held to one side by his partner so that the swing ropes make an angle of 40.0° with the vertical. In such a condition of static equilibrium, what is the tension in the rope?

9.1E+2 N

A projectile is fired at an angle of elevation of 30°. Neglecting air resistance, what are possible angles in flight between the acceleration vector and the velocity vector?

90° and 30°

The net force on an object is in the positive x-direction. Consider the following statements. (I)The object can be moving in the negative x-direction.(II)The object can be speeding up.(III)The object can be slowing down.(IV)The object can be moving in the positive y-direction. Which of the statements are true?

Choose this answer if all the statements are true.

Note the expression: y = A/x3. Which statement is most consistent with this expression?

If x is halved, y is multiplied by eight.

Consider the cosine of any angle between 35° and 40°. If the angle were doubled, what would happen to the cosine of the angle.

It would decrease to less than half its original value.

What forces are included in a free-body diagram for an object?

Only the forces acting on the object.

A car is moving in the positive direction along a straight highway and accelerates at a constant rate while going from point A to point B. If the acceleration is positive, increasing the speed of the car, when does the position where the average speed equals the instantaneous speed occur during the time interval from A to B? Assume the time interval is T.

T/2 from the start of the interval

A sled is on a horizontal surface and a rope with tension T is pulling on it at an angle θ above the horizontal. The sled had mass M and does not move due to the frictional force. In this case the coefficient of friction is μ​s. In terms of the variables given and g, what is the magnitude of the frictional force in this case?

Tcosθ

On a velocity-time graph for a particle, suppose the plot starts at some positive velocity and then follows a straight line to zero at a later time. Which of the following must be true about a position vs. time graph for this same time interval?

The curve will rise steeply at first and as time goes on will level out approaching its highest position value at the later time.

When SI units are plugged into an equation, it is found that the units balance. Which of the following can we expect to be true for this equation?

The equation will be dimensionally correct.

Two baseballs are released at the same time. One is dropped from rest and the other is given an initial horizontal velocity. Which of the following is not true? Ignore atmospheric drag.

The horizontal component of velocity increases at a greater rate than the vertical component of velocity for both while they are both in the air.

A physics student is riding on a train traveling north. Having read about inertia, the student performs an experiment with a golf ball. He reaches over the aisle and drops the ball from rest. Instead of hitting the floor directly below the student's hand, it hits to the north, i.e., forward of that position. Which of the following might be the cause for this to happen?

The train is slowing down.

Starting from rest, a car accelerates down a straight road with constant acceleration a for a time t, then the direction of the acceleration is reversed, (i.e., it is −a), and the car comes to a stop in an additional time t, the time for the whole trip being 2t. At what time, or times, is the average velocity of the car for the trip equal to its instantaneous velocity during the trip?

This occurs at 2 times, 0.5t and 1.5t.

Multiplying a 2-significant-figure number by a 4-significant-figure number and then dividing the product by a seven-significant-figure number yields a number with how many significant figures?

Two SF

Two students are working on the same constant-acceleration problem involving a car undergoing constant acceleration, having started from rest and after a certain time having traveled a distance of 108 m. The students are to find the average velocity. Both students are required to show their work and round any intermediate answers as well as the final answer properly to 3 significant figures. Each rounded answer is to be used in the next step of calculation as they proceed. For the final answer, Student A uses the formula v​avg = (​xf - xi)/(tf - ti) getting the result 7.26 m/s, and Student B uses the formula v​avg = (v​0 + v)/2 getting the result 7.29 m/s. Assuming neither student makes a mistake, which student has the better answer?

Under significant figure rounding, both answers are equally as good.

Vector 1 is 7 units long and is at 70°. Vector 2 is 5 units long and is at 155°. Vector 3 is 3 units long and is at 225°. Which vector has equal-magnitude components?

Vector 3

When we add a displacement vector to another displacement vector, the result is

another displacement.

Three forces, 14.0 N, 25.0 N, and 20.0 N, are acting on a 9.6-kg object. Which of the following forces could also be acting on the object if it is moving with constant velocity?

any of the above

A baseball is thrown by the center fielder (from shoulder level) to home plate where it is caught (on the fly at shoulder level) by the catcher. At what point does the magnitude of the vertical component of velocity have its minimum value? (air resistance is negligible)

at the top of the trajectory

On a position-versus-time graph, the slope of the straight line joining two points on the plotted curve that are separated in time by the interval Δt, is which of the following quantities?

average velocity

Since 1967 the standard definition for the second has been based on which of the following?

characteristic frequency of the cesium-133 atom

In a two-dimensional Cartesian coordinate system the y-component of a given vector is equal to that vector's magnitude multiplied by which trigonometric function, with respect to the angle between vector and y-axis?

cosine

In a two-dimensional Cartesian system, the x-component of a vector is known, and the angle between vector and x-axis is known. Which operation is used to calculate the magnitude of the vector? (taken with respect to the x-component)

dividing by cosine

Which is smallest, an atom, a nucleus, a proton, or an electron?

electron

Which is the correct expression for the force of static friction, where n is the normal force?

fs ≤ μsn

The maximum possible value for the coefficient of static friction is:

greater than 1.00.

In the case of constant acceleration, the average velocity equals the instantaneous velocity:

half-way through the time interval.

A projectile is launched at an angle less than 30° and at speed v. Which will increase the projectile's range more, ignoring atmospheric drag?

increasing the speed of launch by 50%

A block is launched up an incline plane. After going up the plane, it slides back down to its starting position. The coefficient of friction between the block and the plane is 0.3. The time for the trip up the plane:

is less than the time for the trip down.

As I pull a rope connected to a box at constant speed up a frictionless slope, pulling parallel to the slope, the tension in the rope will be:

less than the weight of the box.

The nuclei of atoms contain

protons and neutrons.

Vector is 5 m long and vector is 12 m long. The length of the sum of the vectors must be:

some value from 7 m to 17 m.

Vector points north, and vector points east. If = − , then vector points

south of east.

A strobe photograph shows equally-spaced images of a car moving along a straight road. If the time intervals between images is constant, which of the following cannot be positive?

the acceleration of the car

An x vs. t graph is drawn for a ball moving in one direction. The graph starts at the origin and at t = 5 s the velocity of the ball is zero. We can be positive that at t = 5 s,

the ball has stopped.

Since 1983 the standard meter has been defined in terms of which of the following?​

the distance light travels in a certain fraction of a second

A thrown stone hits a window, but doesn't break it. Instead it reverses direction and ends up on the ground below the window. In this case, we know:

the force of the stone on the glass = the force of the glass on the stone.

A projectile is launched at an angle θ above the horizontal. Three seconds later the projectile is moving the same angle θ below the horizontal. Which of the following (actual values with units, not just algebraic symbols) can be found from the information given?

the initial vertical component of the projectile's velocity

If we know an object is moving at constant velocity, we may assume:

the net force acting on the object is zero.

If the displacement of an object, x, is related to velocity, v, according to the relation x = Av, the constant, A, has the dimension of which of the following?

time

If a is acceleration, v is velocity, x is position, and t is time, then which equation is not dimensionally correct?

v = a/t

Which expression is dimensionally consistent with an expression that would yield a value for time−1? (v is velocity, x is distance, and t is time)

v/x

Which type of quantity is characterized by both magnitude and direction?

vector

Which of the following is an example of a vector quantity?

velocity

Consider the magnitude of the average speed, v​avg, speed, mag, and the magnitude of the average velocity, v​avg, velocity, mag, for the same trip. Which of the following is always true?

v​avg, speed, mag ≥ v​avg, velocity, mag

Two objects, A and B, are placed on an inclined plane that can be rotated to different angles of elevation. A starts to slide at twice the angle of elevation that B starts sliding. The respective coefficients for static friction for A and B are μA and μB. Choose the last answer that is correct.

μA > μB

A box slides up an incline with an angle of elevation θ. When the box reaches its maximum distance up the incline it stops and does not slide down the incline due to friction. What is the minimum value of the coefficient of static friction for this to occur?

μs = tanθ

Human reaction time is usually about 0.18 s. If your lab partner holds a ruler between your finger and thumb and releases it without warning, how far can you expect the ruler to fall before you catch it? The nearest value is​

​16 cm.

Each edge of a cube has a length of 12.7 cm. What is the length of a diagonal of the cube going through the center of the cube?

​8.7 in.

A ball is thrown vertically upwards at 19.0 m/s. For its complete trip (up and back down to the starting position), its average velocity is:

​not given.