Answer: global wind systems
Explanation: Surface currents in the ocean are driven by global wind systems that are fueled by energy from the Sun. Patterns of surface currents are determined by wind direction, Coriolis forces from the Earth's rotation, and the position of landforms that interact with the currents.
A big weight *
Alice has picked up a big weight.
Her friends are talking about the forces that hold it steady.
What forces hold the big weight steady?
A It is not moving, so there are no forces.
OB The only force is gravity, pushing it onto Alice's hand.
C The only force is Alice pushing up, to hold it steady.
D Gravity pushes the weight down and Alice pushes it up.
1 point
Answer:
Gravity pushes the weight down and Alice pushes it up.
Explanation:
In this case, Gravity pushes the weight down and Alice pushes it up. The correct option is D.
module 2 question 8
A seagull flies at a velocity of 11.00 m/s straight into the wind.
(a) If it takes the bird 21.0 min to travel 6.00 km relative to the earth, what is the velocity of the wind?
m/s
(b) If the bird turns around and flies with the wind, how long will he take to return 6.00 km?
s
(c) Discuss how the wind affects the total round-trip time compared to what it would be with no wind.
v = d / t
d = 6 km = 6000 m
t = 21 min = 1260 s
v = Velocity
d = Distance
t = Time
Let B represent the seagull, E represent Earth and W represent the wind.
[tex]V_{BE}[/tex] = 6000 / 1260
[tex]V_{BE}[/tex] = 4.76 m / s
[tex]V_{BW}[/tex] = 11 m / s
[tex]V_{WE}[/tex] = [tex]V_{WB}[/tex] + [tex]V_{BE}[/tex]
[tex]V_{WE}[/tex] = - 11 + 4.67
[tex]V_{WE}[/tex] = - 6.33 m / s
b ) [tex]V_{BE}[/tex] = [tex]V_{BW}[/tex] + [tex]V_{WE}[/tex]
[tex]V_{BE}[/tex] = - 11 - 6.33
[tex]V_{BE}[/tex] = - 17.33
[tex]V_{BE}[/tex] = d / t
- 17.33 = - 6000 / t
t = 346.22 s = 5.77 min
c ) The total time taken in the presence of wind = 21 + 5.77
The total time taken in the presence of wind = 26.77 s
Speed of the seagull in the absence of wind, v = 11 m / s
Total distance travelled = 6 + 6 = 12 km = 12000 m
t = d / v
t = 12000 / 11
t = 1090.9 s
t = 18.18 min
Difference in time = 26.77 - 18.18
Difference in time = 8.59 min
Therefore,
The velocity of the wind with respect to Earth is 4 m / sThe time taken by the seagull to return 6 km is 5.77 minThe time taken without the wind is 8.59 min lesser than in the presence of wind.To know more about relative velocity
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which detail from the text best supports the answer to part a
story: Alexander Hamilton
The detail from the text best supports the answer to part A is Hamilton’s passionate drive pushed him into many confrontations, both physical and political as he sought a lasting legacy.
The part A identifies the central idea of the text which is Hamilton’s strong opinions and tendency to fight relentlessly for his beliefs contributed to the large impact he had as a Founding Father, but also made him several enemies.
Alexander Hamilton was a founding father of United States. He fought in the American Revolutionary War. He drafted the constitution. He was the founder of American financial system.
Therefore, the detail from the text best supports the answer to part A is Hamilton’s passionate drive pushed him into many confrontations, both physical and political as he sought a lasting legacy.
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The longest delivery flight ever made by a twin-engine commercial jet took place in 1990. The plane covered a total distance of 14 890 km from Seattle, Washington to Nairobi, Kenya in 18.5 h. Assuming that the plane flew in a straight line between the two cities, find the magnitude of the average velocity of the plane. Also, find the eastward and southward components of the average velocity if the direction of the plane’s flight was at an angle of 25.0° south of east.
The average velocity of the plane is 804.86 km/h. The eastward and southward components of the average velocity is 729.45 km/h and 340.14 km/h respectively.
The total distance covered by the plane (d) = 14890 km
The time taken for the flight to cover distance (t) = 18.5 hr
The average velocity is calculated by total distance divided by time taken.
[tex]V_{avg} = \frac{d}{t}[/tex]
[tex]V_{avg}=\frac{14890}{18.5}=804.86 km/h[/tex]
The eastward component of average velocity = [tex]V_{x}[/tex]
The southward component of average velocity = [tex]V_{y}[/tex]
[tex]V_{x}= V_{avg}cos\theta[/tex]
[tex]V_{y}= V_{avg}sin\theta[/tex]
Substitute the values and find the components of average velocity.
[tex]V_{x}[/tex] = 804.86*0.90 = 729.45 km/h
[tex]V_{y}[/tex] = 804.86*0.44 = 340.14 km/h
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Steel has a density of 7.8 g/cm³ calculate the mass of a cubic block with a side length 5 cm
Answer:
9750g
Explanation:
Density=78g/cm³
volume= 5×5×5=125cm³
mass=Density×volume
mass=78g/cm³×125cm³
mass=9750g
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Mass can be defined as the amount of matter in an object. If you were to go to another planet or the moon, would the mass of the object increase, decrease, or stay the same? Explain.
Mass does not change thus the object would have the same mass in ay planet or the moon.
What is the mass?
We need to look at the mass of the body as the quantity of matter that we can find in the body. This implies that the more of matter that we can find in a particular object, the more the mass of the object. It is also possible to define the mass as the quantity of the inertia in an object. These are the basic ways that the mass of the object could be considered or understood in this case.
We know that the mass of the object does not change. This is because the quantity of the matter that an object has is not going to change no matter where the object is found whether on the earth or in the moon.
Having said this, we can now agree that the mass of the object would stay the same both on earth and in the moon.
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The resistance of a round copper conductor is 0.2 02. What is the resistance of a copper conductor of equal
length, but four times the diameter?
Resistance of copper wire with four times the diameter is 3.23 Ω.
Formula of resistance is, R= ρl/A.
where, ρ = Resistivity of material
l = Length of material
A= area of material
In first case, resistance of Copper conductor = 0.202 Ω
0.202 = ρ × l /πr²
0.202 = ρ × l/ π (d/2)² …equation 1
In second case, let resistance of copper conductor where diameter is four times be R'
R' = ρ × l /π (d/8)² …equation 2
upon substituting value of equation 1 in 2,
R' = 0.202 × 16
R' = 3.23 Ω
Hence, Resistance of copper conductor with four times diameter is 3.23 Ω
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Evan performed an experiment testing how different wind speeds affect how fast a small cart will roll down a ramp. His data from the experiment is shown in the graph below.
-0.25x + 9
By looking at the graph, we can see that the y-intercept is between 8 and 10.
Slope intercept equation:
y=mx+b
Where;
b= y-intercept ( where the line crosses the y axis )
m= slope ( rise / run)
. What is the resulting acceleration when an unbalanced force of 100. N is applied to a 500 g object?
Answer:
F=ma
100=0,5a
a=200m.s^2
d?
Use the vocabulary words from "Read It" to complete the
following sentences.
We all exert a lot of force every day accomplishing basic
tasks. To make work easier, humans have invented
machines. A (4).
makes work easier with a single
motion. It changes the direction of a force and/or the
amount of work that is applied. One example of this type
of machine is a (5)
which is a beam or bar that
There are three
pivots on a point called a (6)
different classes of this type of machine, but all
three have an (7)
force that is used to
lift the (8)
OUTPUT
STATION
A (4) machine makes work easier with a single motion.
One example of this type of machine is a (5) beam balance which is a beam or bar that.
There are three pivots on a point called a (6) work different classes of this type of machine, but all three have an (7) input force that is used to
lift the (8) object.
What facilitates and expedites our work?Our task is made simpler and quicker by machines.
Contrary to common assumption, using machines does not result in more work being done. They only alter the method of operation. By increasing the amount of force delivered, extending the distance over which the force is applied, or altering the force's direction, machines facilitate work.
By increasing the amount of force delivered, extending the distance over which the force is applied, or altering the force's direction, machines facilitate work.
We are able to gather water thanks to the well-use pulley. We can staple pages together with the aid of a stapler, a machine.
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What is it called when you place the ball in your palm (facing up or sideways) during a dribble?
When you place the ball in your palm (facing up or sideways) during a dribble it is called carrying.
What is carrying in basketball?Carrying occurs when the dribbling player continues to dribble after allowing the ball to come to rest in one or both hands and/or places their hand underneath the basketball. Carrying is a violation of the basketball rules.
There is a type of carrying, known as palming which involves holding the ball in one hand in a grip without allowing it to fall naturally.
Dribbling in basketball is referred to as a repetitive action in which a player uses one hand to bounce the basketball continuously on the court.
There are types of dribbling in basketball which includes:
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Find the resultant of the following vectors:
ASAPPPP
(7) The resultant vector is middle line which is the longest line representing the single effect of the two vectors at both ends.
(8) The resultant vector is any of the lines at the end of the vectors, since any of this line will effectively complete triangle formed by the vectors.
What is resultant vector?A resultant vector is defined as a single vector that produces the same effect as the two or more vectors combined together.
A resultant vector is usually, drawn to join the head of the first vector to the tail of the second in a triangle method of vector addition.
Also, a resultant vector can be determined by applying parallelogram law of vector addition.
Mathematically, a resultant vector can be determined using this formula,
R² = a² + b² - 2ab cosθ
where;
a is the first vectorb is the second vectorθ is the angle between vector a and vector bA resultant vector is always bigger than the two vectors acting together.
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module 1 question 5
If a marathon runner averages 6.6 mi/h, how long does it take him or her to run a 26.22-mi marathon?
h
The time taken to cover the distance during the marathon as shown in the question is 4.0 hours.
What is speed?The term speed has to do with the ratio of the distance that have been covered to the time that have been taken to cover that distance. We know that the distance is a scalar quantity and that the direction of the quantity is not involved. We now need to obtain the speed
Now we have the following;
Speed of the runner = 6.6 mi/h
Distance covered by the runner = 26.22-mi
Speed = distance/time
time = distance/speed
time = 26.22-mi / 6.6 mi/h
= 4.0 hours
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Can you help me with this question.
Given:
he initial velcicty of the runner is
[tex]v_{ir}=\text{ 0 m/s}[/tex]The final velocity of the runner is
[tex]v_{fr}=\text{ 2.6 m/s}[/tex]The time taken is t = 2.1 s
The initial velocity of the motorcycle is
[tex]v_{im}=\text{ 37 m/s}[/tex]The final velocity of the motorcycle is
[tex]v_{fm}=\text{ 44 m/s}[/tex]Required:
Acceleration of the motorcycle.
The difference in distance between runner and motorcycle.
Explanation:
cceleration of the runner is
[tex]\begin{gathered} a_r=\frac{v_{fr}-v_{ir}}{t} \\ =\frac{2.6-0}{2.1} \\ =1.238\text{ m/s}^2 \end{gathered}[/tex]Acceleration of the motorcycle is
[tex]\begin{gathered} a_m=\frac{v_{fm}-v_{im}}{t} \\ =\frac{44-37}{2.1} \\ =3.33\text{ m/s}^2 \end{gathered}[/tex]The distance travelled by the runner is
[tex]\begin{gathered} S_r=v_{ir}t+\frac{1}{2}a_rt^2 \\ =0\times2.1+\frac{1}{2}\times1.238\times(2.1)^2 \\ =2.73\text{ m} \end{gathered}[/tex]The distance travelled by motorcycle is
[tex]\begin{gathered} S_m=v_{im}t+\frac{1}{2}a_mt^2 \\ =37\times2.1+\frac{1}{2}\times3.33\times(2.1)^2 \\ =77.7+7.34 \\ =85.04\text{ m} \end{gathered}[/tex]Thus, the motorcycle travels more distance than the runner.
The
difference between the distance travelled is
[tex]\begin{gathered} \Delta S=S_m-S_r \\ =85.04-2.73 \\ =82.31\text{ m} \end{gathered}[/tex]Final Answer:
The acceleration of the runner is 1.238 m/s^2
The acceleration of the motorcycle is 3.33 m/s^2
The difference in distance between runner and motorcycle is 82.31 m.
9. If you increase the velocity of an object moving in a circle, does it require more centripetal
force or less?
Yes, more centripetal force is required to to sustain an object in circular motion that is moving at a greater velocity.
Answer:
Explanation:
Force:
Fₙ = m*V² / R
m - const
R - const
V ↑
Fₙ ↑
A microwave antenna with a mass of 78 kg sits atop a tower that is 45 m tall. What is the antenna's potential energy?
PLEASE HELP!!!
The potential energy of the microwave antenna with a mass of 78 kg sitting atop a tower that is 45 m tall is 36.69 KJ
U = m g h
U = Potential energy
m = Mass
g = Acceleration due to gravity
h = Height
m = 78 kg
h = 48 m
g = 9.8 m / s²
U = 78 * 9.8 * 48
U = 36691.2 J
U = 36.69 KJ
Potential energy is also called a stored energy. Because an object at rest have high potential energy. Also the higher above the ground the object is placed, higher will be its potential energy.
Therefore, the potential energy of the microwave antenna is 36.69 KJ
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The body of a snorkeler swimming in salt water has a resistance of about 605 Ω . If the snorkeler is unfortunate enough to be struck by the eel, what current will flow through her body?
Resistance of snorkeler, R = 605 Ω.
Current, I = V/R 500/605 = 0.83 A
⇒ I = 0.83 A.
The flow of charge across the cell membrane creates an electric current. Cells control the flow of specific charged elements across membranes using proteins that reside on the cell surface and create openings for specific ions to pass through. These proteins are called ion channels.
For example, if there is a voltage difference between one arm and the other a current will flow through the body. The human body has a higher impedance to DC current than to its AC current. That is, a person can withstand the effects of an electric shock caused by a DC voltage more than he can by an AC voltage. It interferes with the normal functioning of the nervous and muscular systems, causing severe muscle contractions.
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What is the force of gravity between two 1039 kg cars separated by a distance of 25.15 m on an interstate highway?
The force of gravity between the two cars is 1.14 x 10⁻⁷ N.
What is force of gravity?
The force of attraction on a body by earth or force of gravity is defined the gravitational pull of the earth on every object on earth.
Mathematically, the gravitational force between two object is given by;
F = Gm₁m₂/r²
where;
G is universal gravitation constantm is mass of the objectsr is the distance of separation of the objects.F = (6.67 x 10⁻¹¹ x 1039 x 1039)/(25.15)²
F = 1.14 x 10⁻⁷ N
Thus, we can conclude that the force of attraction between two objects in the universe increases with decrease in the distance of separation.
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Gravity is a theory because it is
ANSWER:
Gravity is a theory in that it is a comprehensive explanation of a natural phenomenon that has been tested in a variety of ways.
Which of these does NOT represent the distance traveled by an object?
The bus ride was 30 minutes.
The bus traveled 300 meters.
The motorcycle went 4 miles.
The car drove 35 kilometers.
Answer:
1. The bus ride was 30 minutes
Explanation:
30 minutes = time
meters = distance
miles = distance
kilometers = distance
Explain why six accumulators each of elctromotive foce two volts connect in series can be used to start the engine of a car where as eight dry cell each of electromotive force 1.5v connected in series cannot be used
Electromotive force is the electrical activity produced by a non-electrical source and is measured in volts.. Electrical transducers, which include batteries and generators, transform other forms of energy into electrical energy to produce an emf.
Due to the high internal resistance of the 8-dry cells compared to the low internal resistance of the accumulators, the current generated by the dry cells is too low compared to the current generated by the accumulators. The accumulators will generate the bigger currents required to start the engine because the dry cells' internal resistance is far higher than that of the accumulators. NB. Generally speaking, accumulators have low internal resistance. mostly because the acid therein is a superb conductor.
The effort done by the battery to transform the chemical energy of the cell into electrical energy is what creates the voltage that the electromotive force (e.m.f.) of a battery correlates to (the current in the circuit).
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What does the CARES Act allow regarding charitable contributions?
(1 point)
The CARES Act regarding charitable contributions, allows you to deduct $ 300 in charitable contributions.
CARES act stands for Coronavirus Aid, Relief, and Economic Security act. It is a bill passed by the then U.S. president Donald Trump. It was released as a response to economic fallout due to COVID 19.
According to CARES act, a single tax filer can reduce up to 300 dollars for contributing to charity without the itemization of deductions. If it is a joint tax filing by married individuals the deduction is increased to 600 dollars.
Therefore, the CARES Act allows you to deduct $ 300 in charitable contributions.
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Personal Finance: Role of Financial Institutions Quick Check
1) the sum of your deductible contributions exceeds $300.
2) It allows you to deduct $300 in charitable contributions.
3) Internal Revenue Service
4) a retail or commercial bank
5) It guarantees that you won't lose all of your money.
Explain the concept of an inverse squared relationship?
The concept of an inverse squared relationship explains the behavior of intensity of light and distance of the light source. As the distance of the light source increases, the intensity of light decreases.
What is concept of an inverse squared relationship?
The law of inverse square law says that intensity equals the inverse of the square of the distance from the source.
Mathematically, the formula for the inverse square law is given as;
I ∝ 1/r²
where;
I is the intensity of lightr is the distance from the light sourceWhat is intensity of light?The intensity of light can be defined as the measure of the amount of power emitted by a given surface or reflected by the surface.
Thus, the inverse square law is all about the inverse relation between the intensity of light or power output of a given surface to the distance of the light source.
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7. The initial temperature of a jar of a juice is 80°C and the mass of the juice is 2kg. Susan adds ice cubes into jar in order to cool down the juice to 20°C. What is the minimum number of ice cubes at 0°C required? (Neglect the heat capacity of the jar and assume there is no heat exchange with the surrounding.) Given: Mass of each ice cube = 0.15Kg Specific heat capacity of juice = 4700 J kg¹ °C¹ Specific heat capacity of water = 4200 J kg-¹ °C-¹ Specific heat capacity of fusion of ice = 3.34 x 105 J kg E A. 9 B. 10 C. 11 D. 12
The minimum number of ice cubes at 0°C required to cool down the juice is 11 ice cubes (Option C)
We'll begin by obtainig the heat released by the juice. This can be obtained by
Initial temperature (T₁) = 80 °CFinal temperature (T₂) = 20 °CMass of juice (M) = 2KgChange in temperature (ΔT) = 20 - 80 = -60 °CSpecific heat capacity of juice (C) = 4700 J/KgºC Heat released (Q) =?Q = MCΔT
Q = 2 × 4700 × -60
Q = -564000 J
Next, we shall determin the mass of the total ice. This can be obtained as follow:
Heat capacity of fusion of ice (ΔHf) = 3.34×10⁵ J/kgHeat released = -564000 JHeat absorbed (Q) = 564000 JTotal mass of ice (M) = ?Q = m × ΔHf
564000 = m × 3.34×10⁵
Divide both sides by 3.34×10⁵
m = 564000 / 3.34×10⁵
m = 1.69 Kg
Finally, we shall determine the number of ice cubes. This can be stained as follow:
Total mass of cube = 1.69 KgMass of one cube = 0.15 KgNumber of ice =?Number of ice = total mass / mass of one cube
Number of ice = 1.69 / 0.15
Number of ice = 11 ice cubes
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The Nardo ring is a circular test track for cars. It has a circumference of 12.5 km. Cars travel around the track at a constant speed of 100 km/h. A car starts at the easternmost point of the ring and drives for 22.5 minutes at this speed.
The distance that is covered by the car in unit of kilometers is 37.5 km.
What is speed?The term speed is defined as the ratio of the distance to the time of the movement of an object. We know that speed is a scalar quantity hence we do not look at the direction of the object when we are dealing with the speed.
We have the following;
Speed of the car = 100 km/h
Time taken = 22.5 minutes
To convert the time to hours;
22.5 minutes * 1 hour /60 minutes
= 0.375 hours
Distance = speed * time
= 100 km/h * 0.375 hours
= 37.5 km
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Missing parts;
The Nardo ring is a circular test track for cars. It has a circumference of 12.5km. Cars travel around the track at a constant speed of 100km/h. A car starts at the easternmost point of the ring and drives for 15 minutes at this speed.
What distance, in km, does the car travel?
what should you do every time you are setting up glassware for a vacuum filtration?
Answer:1.Check that there are no cracks or defects in the glassware
2.Ensure that the glassware is designed for use with a vacuum
3.Inspect the tubing for any holes
Explanation:
Verify that the glassware is free from cracks and other flaws, verify that the glass is vacuum-compatible before using it, and look for any holes in the tubing.
What is Vacuum?An area devoid of matter is called a vacuum. The adjective vacuum, which means "empty" or "void," is the source of the word. A location with a vapor pressure significantly below atmospheric pressure might be thought of as an approximate representation of such a vacuum.
The term "partial vacuum" is used to describe an imperfect vacuum, such as one that might exist in a research lab or in space, and is frequently used when physicists discuss the ideal test outcomes that would take place in a complete vacuum, which they more often than not simply refer to as "vacuum" or free space.
Contrarily, any area where the pressure is significantly lower than the pressure difference is referred to as a vacuum in engineering is the application of physics.
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If a batter can apply the same out of maximum force from their hands to each bat to swing it why would the speed of the bat swing decrease as the mass of the bat increases
The speed of the bat swing decrease as the mass of the bat increases because mass is inversely proportional to velocity squared if the centripetal force is constant.
[tex]F_{c}[/tex] = m v² / r
[tex]F_{c}[/tex] = Centripetal force
m = Mass
v = Velocity
r = Radius
Rearranging for v,
v² = [tex]F_{c}[/tex] * r / m
Since [tex]F_{c}[/tex] and r is constant,
v² ∝ 1 / m
Since v² is inversely proportional to m and vice-versa, as the mass of the bat increases, speed of the bat swing decreases.
A centripetal force is responsible for making a body follow a curved path. The direction of centripetal force is perpendicular to the motion and towards the center of curvature.
Therefore, the speed of the bat swing decrease as the mass of the bat increases because mass is inversely proportional to velocity squared if the centripetal force is constant.
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I need help with homework
Given
Mass of the shot, M=50 kg
Its speeed, u=35 m/s
Mass of the smaller shots, m=m'=25 kg
let its velocity be v
To find
The velocity of the smaller shots
Explanation
By conservation of momentum,
[tex]\begin{gathered} Mu=(m+m^{\prime})v \\ \Rightarrow50\times35=(25+25)v \\ \Rightarrow v=\frac{50\times35}{(25+25)} \\ \Rightarrow v=\frac{50\times35}{50} \\ \Rightarrow v=35\text{ m/s} \end{gathered}[/tex]Conclusion
The velocity is 35 m/s.
The recoil experienced when firing a shotgun is a consequence of _____ law.
A large truck travelling at +17 m/s takes 2.5 seconds to come to a complete stop at a red light. What is the acceleration of the truck?Select one:a.- 6.8 m/s^2b.+ 6.8 m/s^2c.+ 42.5 m/s^2d.- 42.5 m/s^2
The acceleration of the truck is -6.8 m/s².
Given data:
The inital speed is u=17 m/s.
The time taken is t=2.5 s.
The truck come to a compelet stop that means the final speed of truck is zero, i.e., v=0 m/s.
The formula for the acceleration is given by,
[tex]\begin{gathered} a=\frac{v-u}{t} \\ a=\frac{0\text{ m/s-17 m/s}}{2.5\text{ s}} \\ a=-6.8\text{ m/s}^2 \end{gathered}[/tex]Thus, the acceleration of the truck is -6.8 m/s².