bob hits a baseball.what two systems are working together to make this happen

The vertical magnetic field is required to keep the rod moving at a constant speed is 0.04T.

A magnetic field, an electric current, a fluctuating electric field, or a vector field around a magnet can all be used to observe magnetic forces. Permanent magnets, including magnetic compass needles, point in the direction of magnetic fields similar to those on Earth. Magnetic fields cause electrically charged particles to move in a helical or circular pattern. This force, which is imparted to electric currents in wires in a magnetic field, is what drives the functioning of electric motors. When the magnetic field surrounds a permanent magnet or a wire carrying a steady electric current in one direction, it is referred to as a magnetostatic field and is stationary.

Calculations:

Given mass of rod ,m=0.2kg

current carrying= I = 10A

Separation between rails =d = 0.5m

coefficient of kinetic friction ,uk= 0.1

The force of magnetic field (F) is perp.r to the magnetic field.

Let required magnetic field be B.

Now balancing forces in y-direction,

        N=mg

And. in x-direction,

        F=f

       IBd= [tex]u_{k}[/tex]N

       IBd=[tex]u_{k}[/tex]mg

       B=[tex]\frac{0.1x0.2x10}{10x0.5}[/tex]

      B= 0.04T

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(c) The fundamental frequency of one of the organ pipes will go up or increase.

When pressured air is forced into an organ pipe, it echoes at a particular pitch, generating the sound of the pipe organ. Each pipe has been adjusted to a particular pitch on the musical scale.

An outdoor pipe organ is a type of musical instrument used to perform music. It sounds quite serene and produces some calming tones.

The organ pipe produces the sound of the outdoor organ. The wavelength of the sound is also dependent on the length of the pipe. The fundamental frequency of one of the organ pipes will grow as the speed of the sound increases as the ambient air temperature rises.

The correct option is (c).

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The acceleration lasts 0.0077 seconds and is equivalent to 8450 m/s².

The rate at which an object's position changes with respect to time is defined as velocity.

Because it consist of both magnitude and direction, it is a vector quantity. Speed is a scalar quantity that represents the magnitude of velocity. The SI unit of velocity and speed is m/s.

Acceleration is the measure of how quickly a velocity varies over time. It is also a vector quantity. A negative sign of acceleration indicates that the velocity of the body is decreasing with time.  

Given in the question

Initial speed = u = 0 m/s ( as the firework starts from rest)

Final velocity = v = 65 m/s

Distance traveled = 0.25 m

B) Acceleration

Using the third equation of motion,

[tex]v^{2} -u^{2} =2as[/tex]

Put in the value, we get

(65)² - (0)² = 2a(0.250)

0.5a = 4225

a = 8450 m/s²

As a result, fireworks accelerate at 8450 m/s².

A) Time the acceleration lasts

Acceleration is calculated as (Final Velocity - Initial Velocity)/Time.

Put in the values, we get

8450 = 65/time

Time = 65/8450

Time = 0.0077 seconds

Hence, the acceleration lasts for 0.0077 seconds and is 8450 m/s².

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The directions of the vectors for velocity and acceleration will be [b] the velocity vector points to the right and the acceleration vector points to the left.

The velocity vector is always pointing in the direction that the object is moving. Therefore, from our vantage point, the direction of velocity is to the right.

When an object experiences positive acceleration, the acceleration vector points in the object's motion direction.

When an object experiences a negative acceleration, the acceleration vector is in the opposite direction as the object's velocity. Therefore, from our vantage point, the direction of velocity is to the left.

The rate at which an object's position changes is called its velocity vector. The rate at which an object's velocity changes is called its acceleration vector.

As a result, the vectors for acceleration and velocity point in opposite directions.

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A train slows down as it pulls into a station, if the train is moving from your left to your right, what are the directions of the vectors for velocity and acceleration?

[a] the velocity points to the left and the acceleration vector also points to the left

[b] the velocity vector points to the right and the acceleration vector points to the left

[c] the velocity vector points to the left and the acceleration vector points to the right

[d] the velocity vector points to the right and the acceleration vector also points to the right

Electron and proton have charge which is option (a) and (c) .

As electron and proton have charges -e and +e respectively and photon has no charge.

Therefore, only electron and proton have charge not photon .

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ohm's law is a formula used to calculate the relationship between voltage, current, and resistance in an electrical circuit. To students of electronics, ohm's law (e =ir) is as fundamentally important as einstein's relativity equation ( e= mc2) is to physicists. e = l x r. rest is on Goo gle

If a certain piece of metal is cooled, it will conduct electricity better, this statement is theory whereas, the amount of electric current that passes through a conductor is directly proportional to the voltage is known as law.

A hypothesis is a statement that may be true or false. A theory is a well-supported explanation of observations or data. A scientific law is a statement that explains the relationship between variables. Hypothesis is a statement that is given before performing an experiment. It can be true or false after we perform an experiment. When a number of experiments can be performed and the hypothesis comes out true then theory is evolved. When the statement is verified after performing large number of experiments, it becomes a law.

So we can conclude that if a certain piece of metal is cooled, it will conduct electricity better, this statement is theory whereas, the amount of electric current that passes through a conductor is directly proportional to the voltage is known as law.

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Answer:

index fossil, any animal or plant preserved in the rock record of the Earth that is characteristic of a particular span of geologic time or environment. A useful index fossil must be distinctive or easily recognizable, abundant, and have a wide geographic distribution and a short range through time. Index fossils are the basis for defining boundaries in the geologic time scale and for the correlation of strata. In marine strata, index fossils that are commonly used include the single-celled Protista with hard body parts and larger forms such as ammonoids. In terrestrial sediments of the Cenozoic Era, which began about 65.5 million years ago, mammals are widely used to date deposits. All of these animal forms have hard body parts, such as shells, bones, and teeth, and evolved rapidly.

Explanation:

Change in length in meters is 0.21 m

volume is given by

 [tex]V_{f} = lwh\\[/tex]

v = volume  [tex]V_{f}[/tex] = Final  volume , [tex]V_{i}[/tex] = initial volume

l = length

w = width

h = height

change in volume expansion,

[tex]V = \beta V_{i} T[/tex]

where

t = change in temperature

[tex]\beta[/tex] = coefficient of volume expansion

coefficient of volumetric expression defined as increasing volume per unit, original volume per Kelvin rising temperature.

[tex]\beta \\[/tex] = 210×10⁻⁶ C⁻¹

[tex]V_{i} = lwh_{i}[/tex]  

[tex]V_{f} - V_{i} = \beta V_{i}T[/tex]

on solving we get,

[tex]h_{f} =[/tex] 210×10⁻⁶ × 1 + 1000 = 1000.21m

Change in length=  [tex]h_{f} -h_{i}[/tex]  = 0.21 m

Change in length in meters is 0.21 m

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c.  it fails to state the original cause

As we all know as we know the universe is created  billion years ago when a small fire ball that exploded.

Big Bang theory is discovered by the George Lemaitre.

It is the explanation "how the universe began."

It states that universe starts from a tiny  point then expanded to grow more larger and it is still expanding.

Big Bang Theory cannot explain Galaxy formation. It cannot solve the problem of universe of origination because it didn't tell where the singular point of Big Bang came.

c. it fails to state the original cause

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The ion rocket engine give an acceleration to the space probe of: 0.001 m/s²

To solve this exercise, the formula and procedure to be applied is:

F = m * a

Where:

Information about the problem:

Applying the force formula and isolating the acceleration, we get:

F = m * a

a = F/m

a = 1 N /1000kg

a =  1 kg * m/s² / 1000kg

a = 0.001 m/s²

It is the physical magnitude that expresses the effort necessary to move the mass of one kilogram with an acceleration of one meter per second squared, this is expressed in units of the international system in Newton.

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Mr. spoke is travelling with speed v = 9.4c.

Mr. spoke is apparently unknowing of  theory of special relativity by Einstein. The theory states that moving clock tick slower than stationery clock.

Time elapse =∆t = 3 weeks

(In earth stationery frame)

Time ellipse= ∆t' = 1 week

(In the frame of rocket)

∆t' = ∆t'/γ

1/y² = 1 - v²/c²

∆t'²/∆t² =

=1²/3²

=1/9

c= 3×10⁸m/s

on solving above equation we get :

v = 9.4c

He was spreading around at close to the speed of light.

Experience significant time dilatation.

He is travelling with speed  v = 9.4c.

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voltage drop can occur both the high current and control circuits.

Voltage drop - it is the loss of voltage by caused by the flowing current through resistance.

As any length of wires will have resistance running a current through the direct circuit resistance will cause the voltage drop.

It occurs voltage at the end point is less then the starting point.

control circuits - The circuit which carries only the electric signals directing performance of control device not power that device controls.

voltage drop can occur across both the high-current and control circuits; however, the control circuit is more susceptible to voltage drop due to the much larger amount of current flowing in the circuit.

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The radius of curvature of the proton's path while in the field is [tex]66.67[/tex]  × [tex]10^{-2}[/tex].

b) Let R = radius curvature of protons path. Then,

relation b/w B, R, and v is: -

[tex]B = mv/eR\\R=mv/eB[/tex]

[tex]R=\frac{1.6*10^{-27} * 20*10^{6}}{1.6*10^{-19}*0.3 }[/tex]

[tex]R =66.67[/tex]× [tex]10^{-2}[/tex]

Hence, the radius of curvature of the proton's path while in the field is [tex]66.67[/tex] × [tex]10^{-2}[/tex].

The magnetic influence on moving electric charges, electric currents and magnetic materials is described by a magnetic field, which is a vector field. A force perpendicular to the charge's own velocity and the magnetic field acts on it when the charge is travelling through a magnetic field.  The magnetic field of a permanent magnet pulls on ferromagnetic substances like iron and attracts or repels other magnets. A magnetic field that varies with location will also exert a force on a variety of non-magnetic materials by changing the velocity of those particles' outer electrons. Electric currents, like those utilized in electromagnets, and electric fields that change in time produce magnetic fields that surround magnetized things.

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The direction of the bird's velocity can be adjusted so that the wind and the resulting bird velocity will both be in the southerly direction.

(a) The bird should fly at an angle of roughly South 23.58° East if it wants to move directly southward in relation to the earth.

(b) The bird would need around 5.46 hours to fly 500 kilometres from North to South.

The components of the velocity are v(x) and v(y).

The magnitude of the velocity of the bird is 100 km/h

The orientation of the bird corresponds to that of North and South.

The magnitude of the velocity of the wind is 40 km/h

East-west is the direction of the wind.

(a) The component vector of the two velocities are;

The velocity of the bird, v(y) = -100(j)

The velocity of wind, v(x) = 40(i)

If the bird has a component of velocity to accommodate the wind velocity, the direction of its movement will be southerly.

Let θ be the angle of the direction of the bird relative to the negative x-axis, therefore:

-100(j) × cos(θ) = -40·i

θ = cos⁻¹(40/100)

θ ≈ 66.42° in the third quadrat, given that both the y, and x, values are negative.

In the South-West direction, the angle is:

90 - 66.42 ≈ 23.58°

Therefore, to fly directly southward relative to the ground, the bird should fly in the direction of south 23.58° east.

(b) The following is given as the component of the bird's southerly velocity when traveling in the new direction:

v(s) = 100 × sin(θ)

Hence,

Southward velocity,  v(s) = 100 × sin(66.42°)

The time t it takes to travel 500 km, is given as:

d = v(s)t

500 = 100 × sin(66.42°)(t)

t = 5.46 hrs

The bird would need 5.46 hours to fly 500 kilometres from North to South.

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The complete question is mentioned below:

Canada geese migrate essentially along a north–south direction for well over a thousand kilometres in some cases, traveling at speeds up to about 100 km/h. If one goose is flying at 100 km/h relative to the air but a 40-km/h wind is blowing from west to east,

(a) at what angle relative to the north–south direction should this bird head to travel directly southward relative to the ground?

(b) How long will it take the goose to cover a ground distance of 500 km from north to south? (Even on cloudy nights, many birds can navigate by using the earth’s magnetic field to fix the north–south direction.)

When gas particles contact with one another at a fixed temperature and volume, the average kinetic energy of the gas remains constant. Given that the temperature stays constant, this is the case. This characteristic gives us some understanding of the kinetic energy of the particles; for example, if the temperature rises, we may predict that the kinetic energy will follow suit. However, this kind of energy does not change if the temperature stays constant.

A particle or an item that is in motion has a sort of energy called kinetic energy. When work, which entails the transfer of energy, is done on an object by applying a net force, that object acquires kinetic energy.

Mass and speed are the two fundamental variables that influence kinetic energy. Why? Because an object's motion is dependent on both its velocity and its mass, though velocity plays a larger role in motion.

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Answer:

It's one meter long and has 100 cm and 39.4 inchs

Explanation:

At a point halfway between the center and any vertex, the field is stronger.

An equilateral triangle with side L is formed by the bend of a wire carrying a current I.

The magnetic field created by a straight wire is given as:

[tex]B = \frac{ \mu_{0} I}{2 \pi a}[/tex]

The cosines of the complementary angles are identical to the sines of the angles that appear in that equation.

For the distance "a" from the wire to the field point,

We obtain:

[tex]tan{~}30^{\circ} = \frac{a}{L/2}\\a = 0.2887L[/tex]

We have one whole side of the triangle that generates a magnetic field at the center of the triangle is [tex](\frac{ \mu_{0} I(1.732)}{4 \pi a} )[/tex].

Now, the near side of a triangle will be at a geometrically equivalent location and will be half as far from point P(b).

Then the field at P(b) is:

[tex](\frac{ \mu_{0} I(1.732)}{4 \pi a} )= \frac{2 \mu_{0} I (1.732)}{4 \pi a}[/tex]

A P(b) field is created by the two half-sides that are cross-hatched which is:

[tex]2(\frac{2 \mu_{0} I(1.732)}{4 \pi a} )= \frac{4 \mu_{0} I (1.732)}{4 \pi (0.2887L)}=\frac{6 \mu_{0} I}{ \pi L}[/tex]

We already have evidence that the field at P(b) is stronger because the remaining triangle will contribute a little bit more field in the same direction.

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w = wavelength = h / mv

Where h = Planck’s constant = [tex]6.626*10^{-34} J s[/tex]

m = mass of golf ball = 45.9 g = [tex]45.9*10^{-3} Kg[/tex]

v = velocity of ball = 72.0 m/s

Hence, w = ([tex]6.626*10^{-34}[/tex]) / ( [tex]45.9*10^{-3}*72[/tex])

wavelength = [tex]2.0*10^{-34} m[/tex]

The distance over which a periodic wave's shape repeats is known as the wavelength in physics. Along with other spatial wave patterns, it is a characteristic of both traveling and standing waves. The distance between two adjacent crests, troughs, or zero crossings on the wave that correspond to successively in the same phase. The spatial frequency is the reciprocal of wavelength. The Greek letter lambda (λ) is frequently used to represent wavelength. The term wavelength is also occasionally used to refer to modulated waves, their sinusoidal envelopes, or waves created by the interference of several sinusoids. A spectrum is the term used to describe the range of wavelengths or frequencies for wave phenomena. The term was originally used to describe the electromagnetic spectrum, but it is now now used to describe the sound spectrum and vibration spectrum.

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By relativistic momentum, the proton speed is 1.93 x 10⁵ m/s.

We need to know about relativistic momentum to solve this problem. The rest energy of the object can be determined by

P = m₀ . v/ √(1 - v²/c²)

where P is relativistic momentum, m₀ is rest mass, c is speed of light (3 x 10⁸ m/s) and v is speed of object.

From the question above, we know that :

mp = 1.6 x 10¯²⁷ kg

me = 9.1 x 10¯³¹ kg

c = 3 x 10⁸ m/s

ve = 0.75c

Find the relativistic momentum of electron

P = me . ve/ √(1 - ve²/c²)

P = 9.1 x 10¯³¹ . 0.75c / √(1 - (0.75c)²/c²)

P = 2.0475 x 10¯²² / 0.66

P = 3.1 x 10¯²² kg.m/s

Find the speed of proton

P = mp . vp/ √(1 - vp²/c²)

3.1 x 10¯²² = 1.6 x 10¯²⁷ . vp / √(1 - vp²/c²)

vp = 193892.05 x √(1 - vp²/c²)

squared

vp² = 3.76 x10¹⁰ -  3.76 x10¹⁰vp²/c²

(1 + 3.76 x10¹⁰/c²) vp² = 3.76 x10¹⁰

(1.0) vp² = 3.76 x10¹⁰

vp = √(3.76 x10¹⁰)

vp = 1.93 x 10⁵ m/s

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The final velocity of the ball when it is caught is 20.58 m/s

Velocity is the rate of change of displacement.

To calculate the final velocity of the ball when it is caught, we use the formula below.

Formula:

Where:

From the question,

Given:

SUbstitute these values into equation 1

Hence, the  final velocity of the ball when it is caught is 20.58 m/s

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The shock wave from the meteoroid in the lower atmosphere has a Mach angle of 0.948°.

(a) The meteoroid's speed [tex]v_s=20 \mathrm{~km} / \mathrm{s}[/tex]

[tex]$=20 \times 10^3 \mathrm{~m} / \mathrm{s}$[/tex]

Air sound wave speed [tex]&v=331 \mathrm{~m} / \mathrm{s} \\[/tex]

Speed of the shock wave in Mach [tex]&\qquad \theta=\sin ^{-1}\left(\frac{v}{v_s}\right)[/tex]

                                                            [tex]$$\begin{aligned}&=\sin ^{-1}\left(\frac{331 \mathrm{~m} / \mathrm{s}}{20 \times 10^3 \mathrm{~m} / \mathrm{s}}\right) \\&=0.948^{\circ}\end{aligned}$$[/tex]

Hence, 0.948° is the Mach angle of the shock wave from the meteoroid in the lower atmosphere.

A meteoroid's speed can be loosely broken down into three categories: slow, medium, and fast.

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Dynamics sound helps differentiate between the sound of a fire truck, an ambulance and an 18-wheeler.

Elements allude to the din or delicateness of music. Elements offer a method for showing articulation in printed music. They help to drive the profound substance of music through volume and force. Elements can likewise be shown at the large-scale level for a piece of music in general. This may be just a single time toward the beginning, or a few times all through in the event that the din changes during various segments. Static elements are melodic directions that advise us to play the music at a specific volume that doesn't change. As such, don't get stronger or calmer, play each note at a similar volume as the final remaining one.

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The barometric pressure (BARO) sensor works in conjunction with the manifold absolute pressure (MAP) sensor to provide constant pressure difference information to the PCM.

The Manifold Absolute pressure (MAP) sensor is used by the Powertrain Control Module (PCM) for engine load entry. The PCM makes use of this input, as well as others, to calculate the correct quantity of gasoline to inject into the cylinders. The MAP sensor measures the absolute strain within the intake manifold of the engine.

Barometric pressure is the size of air strain in the atmosphere, in particular the size of the load exerted by way of air molecules at a given point on this planet.

The Manifold Absolute pressure sensor performs 'double obligation' as a barometric stress sensor as soon because the key's turned on. With the key became on (prior to the engine starting) there is no vacuum inside the engine applied to the MAP sensor therefore its sign to the ECM will become a BARO studying useful in determining air density.

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The electric force acting on a 7.80 nc charge that is located 1.69 m from a 4.54 nc point charge is: 1.115*10^-7 N

To solve this exercise the electric force formula and the procedure we will use is:

F = (k * q1 * q2)/r²

Where:

Information about the problem:

By converting the the values of the charges (q1) and (q2) from (nC) to (C) and we have that:

q1= 7.80 nC * 1 C/ 1*10^ 9 nC

q1= 7.8*10^ -9 C

q2= 4.54 nC * 1 C/ 1*10^ 9 nC

q2= 4.54 *10^ -9 C

We apply the electric force formula we have:

F = (k * q1 * q2)/r²

F = [(9 *10^9 N*m²/C² * (7.8*10^ -9 C) * (4.54 *10^ -9 C)]/ (1.69 m)²

F = 3.187*10^-7 N*m² /2.8561 m²

F = 1.115*10^-7 N

In physics the electric force is the force that attracts or repels two charges (q) separated at a distance called (r), this is expressed in the international system of units in Newton.

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The initial velocity with which the rock was launched is 41.16 m/s and the maximum height achieved by the rock is 86.4 m.

The three equations of motion are -

v = u + at

S = ut + 1/2 at²

v² - u² = 2aS

Given is a rock launched from ground vertically upwards reaching its highest point after 4.2 s of being launched. Therefore, we can write -

Time taken to achieve maximum height [t] = 4.2 sec

Acceleration [a] = - 9.8 m/s²

Assume that the initial velocity is u.

Therefore - at maximum height S[max],  t = 4.2 s

Now, at maximum height, final velocity (v) will be zero.

From the first equation of motion -

v = u + at

0 = u - gt

u = gt

u = 9.8 x 4.2

u = 41.16 m/s

The initial velocity of rock was 41.16 m/s.

The maximum height achieved by the rock -

S[max] = ut + 1/2 at²

S[max] = 41.16 x 4.2 - 0.5 x 9.8 x 4.2 x 4.2 = 172.87 - 86.44 = 86.4 m

Therefore, the initial velocity with which the rock was launched is 41.16 m/s and the maximum height achieved by the rock is 86.4 m.

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By the velocity, they will travel 6.875 m and the dog catches the man at 2.08s.

We need to know about velocity to solve this problem. Velocity can be determined as the distance traveled divided by time interval. It can be written as

v = s / t

where v is velocity, s is distance and t is the time interval.

From the question above, we know that.

v man = 1.5 m/s

v dog = 3.3 m/s

to = 2.5s

Determine the distance traveled by man when the dog waits

so = vman . to

so = 1.5 x 2.5 = 3.75 m

Find the man's total distance

total distance = distance after dog run + distance when the dog waits

total distance = vman . t + 3.75

We know that the total distance by man's will be caught by the dog, Thus

total distance = vman . t + 3.75

v dog . t = 1.5t + 3.75

3.3t = 1.5t + 3.75

1.8t = 3.75

t = 2.08 s

Find total distance

total distance = vdog . t

total distance = 3.3 x 2.08

total distance = 6.875 m

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The water in the Cuyahoga river flows at a speed of 5.4 kilometers/hour. If you decide to canoe down the river a distance of 16 kilometers, then it would take 2.96 hours.

The total distance covered by any object per unit of time is known as speed. It depends only on the magnitude of the moving object.

As given in the problem, the water in the Cuyahoga river flows at a speed of 5.4 kilometers/hour. If you decide to canoe down the river a distance of 16 kilometers,

The time period for canoeing 16 kilometers = 16 kilometers / 5.4 kilometers/hour

                                                                         =2.96 hours

Thus, it would take 2.96 hours to canoe down the river a distance of 16 kilometers.

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Answer:

C. 18 s

&

B. -7 m

Explanation:

A. 12 m/s, East is a vector. It says "East" so it would be a vector. Therefore this is not our answer since it's a vector and the question is asking for which one is not a vector.

B. It says "7 m". I think that means 7 meters. That's a length. There is no direction. It's not 7 meters up, or to the east, or north. So, with no direction, it's not a vector. Therefore this is not our answer.

C. For this one it says ""18 s". I think that means "18 seconds". Since this one is not mentioned "direction" meaning it's not a vector. Since the question is asking for the ones that are not a vector this would be another answer.

D. Since this one says "miles" it means it has a direction since it has a direction it is probably a vector, since it's a vector it wouldn't be our answer. Therefore this is not our answer.