The force acting on the object will be 32 N.
Newton's second law of motion states that, "the force is equal to the change in momentum per change in the time". The mathematical form of the law is given below.
[tex]F = \frac{dP}{dt}=\frac{d(mv)}{dt}=m\frac{dv}{dt}=ma[/tex]
Where P = momentum, t = time, m =mass, v = velocity, a = acceleration and F = force.
The mass of the object is 4 kg and acceleration is 8 m/s^2. Substitute the values in the equation and we will get the force.
F = ma
F = 4 kg * 8 m/s^2
F = 32 kg.m/s^2
F = 32 N
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10.A fairground ride spins its occupants inside a large teacup. If the radius of the
circular path is 10m and the acceleration is 1.5g, what is the speed of the riders?
Radial acceleration is inversely related to the radius of the curved pathway and directly proportional to the square of the linear speed. The ratio of the square of the angular speed to the radius of the curved pathway is directly proportional to the radial acceleration.
Explain about the radius and acceleration?This is the acceleration of an object moving at speed v within a circle of radius r. Therefore, as you may have experienced while driving a car, centripetal acceleration is greater at high speeds and in acute curves (smaller radii). y.
We can argue that as the radius increases, the centripetal acceleration of the item moving in a circle falls exponentially. Along the radius, the centripetal acceleration's magnitude diminishes.
The centripetal acceleration would be decreased if the radius were decreased while all other factors remained constant, but it would be increased if the speed were increased while all other factors remained constant.
The radius of the circular path is 10m and the acceleration is 1.5g the speed of the rider is 1.82 m/s/s.
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What is Momentum ?
Ty :))
Answer:
Momentum can be well defined as the measure of the kinetic energy of the object. In simple words, the momentum is the product of mass and velocity.
What would be the acceleration if the force in question 1 were doubled?
A person on a cruise ship is doing laps on the promenade deck. On one portion of the track the person is moving north with a speed of 3.9 ms relative to the ship. The ship moves east with a speed of 12 ms relative to the water.
The resultant speed of the person on the cruise ship is 12.62 m/s.
What is resultant speed?The resultant speed of an object is the single speed which can effectively represent two or more speed of the object.
The magnitude of the resultant speed of the person on a cruise ship is calculated as follows;
Vr² = Va² + Vb²
where;
Vr is the resultant speed of the personVa is the speed of the person to the northVb is the speed of the person to the eastSubstitute the value of the north speed and east speed to determine the resultant speed of the person on the ship.
Vr = √Va² + Vb²
Vr = √[(3.9 m/s)² + (12 m/s)² ]
Vr = 12.62 m/s
Thus, for a person on a cruise ship is doing laps on the promenade deck at a speed of 3.9 m/s to the north and the speed of the ship 12 m/s to the east, the resultant speed is 12.62 m/s.
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The complete question is below:
Find the resultant speed of the person
Marco and his sister are rummaging through a large box of books. Their younger brother also wants to see what’s inside the box. Marco pulls the box away from his brother, applying a force of 38 N to the left. His sister helps him by applying an additional force of 36 N to the left. Their brother applies a force of 35 N to pull the box in the opposite direction. The box weighs 22 kg. Determine the acceleration of the box.
By applying net force formula, the acceleration of the box is 1.8 m/s²
What is Acceleration ?Acceleration is the velocity change per time taken. It is a vector quantity and it is measured in m/s²
Given that Marco pulls the box away from his brother, applying a force of 38 N to the left. His sister helps him by applying an additional force of 36 N to the left. Their brother applies a force of 35 N to pull the box in the opposite direction. The box weighs 22 kg.
F = ma
Where
F = Net force = sum of the left forces - sum of the right forces m = 22 Kga = ?To determine the acceleration of the box, substitute all the parameters into the formula
(38 + 36) - 35 = 22 a
74 - 35 = 22a
39 = 22a
a = 39/22
a = 1.77 m/s²
Therefore, the acceleration of the box is 1.8 m/s² approximately.
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4.
Both solenoids and electromagnets
produce magnetic fields using
A electric current and coiled wires
B
compasses and magnetic fields
C coiled wires and a ferromagnetic core
D electric current and a battery
Both solenoids and electromagnets produce magnetic fields using electric current and coiled wires. The correct option is A
What are electromagnets?An electromagnet can be defined as a type of magnet in which the magnetic field is produced by an electric current.
Electromagnets usually consist of wire wound into a coil.
Both solenoids and electromagnets produce magnetic fields using electric current and coiled wires.
The simple arrangement and construction of electromagnets requires an insulated copper wire, iron rod and battery.
Electromagnets has some advantages which includes :
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hd 93083. note that planet b is in this star’s chz. now in fact this planet has a mass of at least 0.37 jupiter masses. is this planet a likely candidate to have life like that on earth? why or why not?
True now in fact this planet has a mass of at least 0.37 jupiter masses. is this planet a likely candidate to have life like that on earth
Due to its greater mass, the planet would be subject to a stronger gravitational pull. The gravitational pull depends on two things:
Weight of the body
Distance
The planet's mass is 118 times more than Earth's, therefore the life forms there would be very different from those on Earth.
The supplied response is accurate since the planet's is far greater than the earth's, and it also relies on the planet's distance from its star in the solar system and the quantity of heat that it receives. Europa would be submerged in water as a result of the ice being warm enough to melt.
Oort cloud perturbations are not considered to be extinction events.
Supernovas are extinction-level events.
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calculate the percent efficiency of a motor that lifts a 50 n weight, 5 meters in 10 seconds. the motor is run by a 9v battery with 3 amperes of current.
The efficiency of the motor is 92.6%
The input energy comes from the motor.
W_in = P . t
Where:
P = V. i
= 9 volt. 3 A = 27 Watt
Hence,
W = 27 watt . 10 seconds = 270 Joules.
The output work is the potential energy.
W_out = F . s
= 50 . 5 = 250 Joule.
The efficiency is calculated as:
Efficiency = W_out / W_in x 100%
= 250/270 x 100% = 92.6%
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Did DART apply a balanced or unbalanced force to the satellite during the collision? What evidence supports your answer?
Answer:
A collision is an interaction between two objects that have made contact (usually) with each other. As in any interaction, a collision results in a force being applied to the two colliding objects. Newton's laws of motion govern such collisions
An interaction between two items that have made contact with one another is referred to as a collision. A collision exerts a force on the objects interacting, just like any other interaction. Such collisions are regulated by Newton's laws of motion.
What is collision?In physics, a collision, which is also known as an impact, is the abrupt, violent coming together and in near vicinity of two bodies, such as two pool cues, a golf club and a ball, a hammer as well as a nail, two railroad cars when linked, or a falling item and a floor.
The force and the amount of time the objects are in touch, in addition to the materials the two objects are made of, have an impact on the outcome of the impact. Generally,is common knowledge that a hardened steel ball bounced on a steel plate would rebound almost to the original position from where it was dropped, while a ball made of putty and lead will not.
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what is the total work wfric done on the block by the force of friction as the block moves a distance l up the incline? express the work done by friction in terms of any or all of the variables μ , m , g , θ , l , and f1 .
The work done by friction W = (F1 - mg sin θ) L, W = -μ mg cos θ L.
Use Newton's Second Law to find the force of friction. In these tasks, the X-axis will be parallel to the plane and the Y-axis will be perpendicular to the plane:
Y-Axis
N - =[tex]w_{y}[/tex]
N = W_{y}
X axis
F1 - fr - Wₓ = 0
fr = F1 - Wₓ
Let's use trigonometry to find the components of the weight
sin θ = Wₓ / W
cos θ = W_{y} / W
Wₓ = W sin θ
W_{y} = W cos θ
We substitute
fr = F1 - W sin θ
Work is defined by
W = F .dx
W = F dx cos θ
Since the friction force is in the negative direction parallel to the plane and the displacement along the plane is positive, the angle is 180° and cos θ = -1
W = -fr x
W = (F1 - mg sin θ) L
Another way to calculate is
fr = μ N
fr = μ W cos θ
the work is
W = -μ mg cos θ L.
Zero work can occur in any of the following situations When a single force is applied but no displacement. There are gaps but the power of the individual is not showing. A single force is applied in a direction perpendicular to the direction of displacement.
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A car travels downtown on the freeway with a constant speed of 10 miles/hour. if the car travels for .5 hours , how far away is downtown?
The downtown is 5 miles far away, if the car travels at 10 miles / hour for 0.5 hours.
v = d / t
v = Velocity
d = Distance
t = Time
v = 10 mi / hr
t = 0.5 hr
d = v * t
d = 10 * 0.5
d = 5 mi
Velocity of the car is the rate of change of position of the car. In simple words it can be said as velocity is used to calculate the distance covered in a given amount of time.
Therefore, the downtown is 5 miles far.
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When a football player catches a football. Time interval or a time instant? (Please give me the right answer)
what is the coefficient of static friction between m1 and m2 (call this s1) and between m2 and the wall (call this s2) if the minimum force fmin required to keep the blocks from breaking loose and sliding under the influence of gravity is fmin
The static coefficient of friction between m1 and m2 and m2 and the wall (designated as s1 and s2, respectively) if the minimum force F minimum necessary to prevent the blocks from separating and sliding under the action of gravity is F minimum.
What is static friction coefficient?
The ratio of limiting friction to the usual reaction between the surfaces is known as the coefficient of static friction.
This equation yields the minimum coefficient of static friction:
When the radius of curvature R = 190 m and the vehicle's speed V is 72 km/h (20 m/s), the smallest value of the coefficient of static friction Typically, it is represented by the Greek letter mu ().
In terms of math, is equal to F/N, where F stands for frictional force and N for normal force. The coefficient of friction has no dimensions because both F and N are measured in units of force (such as newtons or pounds). friction equals 0.21.
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how does a coal-fired power plant use the energy in coal to produce electricity? burning coal heats wires to very high temperatures, which then generate electricity. burning coal generates light that is converted into electricity. burning coal heats water and creates steam that turns the blades of a turbine and generates electricity. burning coal heats air that spins the blades of a turbine and produces electricity.
Coal is burned to create steam, which is then used to generate electricity at coal-fired power stations. Under extreme pressure, the steam generated enters a turbine, which turns a generator to provide power. In order to restart the process, the steam is then cooled, condensed back into water, and fed back into the boiler.
For example, the Kingston Fossil Plant near Knoxville, Tennessee, uses coal to heat its boilers to around 1,000 degrees Fahrenheit in order to produce high-pressure steam as a practical illustration of this.
How is energy generated by burning coal?
Whether bituminous, subbituminous, or lignite, they are all burned in coal-fired power plants. The heat generated by coal combustion is utilized to turn water into high-pressure steam, which drives a turbine and generates electricity.
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Drag each label to the correct location on the figure. Not all labels will be used.
Match the function to the correct part of the neuron.
passes electrical signals
to another neuron
contains the nucleus
and cell organelles
receives signals from
other neurons
conveys electric signals
across a long distance
protects and
insulates the axon
The function should be matched to the correct part of the neuron as follows:
Axon: passes electrical signals to another neuron.Cell body: contains the nucleus and the cell organelles.Dendrites: receives signals from other neurons.Action potential: conveys electrical signals across a long distance.Myelin: protects and insulates the axon.What is a neuron?A neuron can be defined as a nerve cell that's saddled with the responsibility of transmitting electrical signal (impulses) down an axon across a cellular membrane of the body of a living organism through an action potential.
In Science, the neuron comprises different parts and these include the following:
DendritesCell bodyMyelinAction potentialAxonIn conclusion, we can reasonably infer and logically deduce that a neuron transmits electrical signal (impulses) down an axon (a long, tail-like structure) across a cellular membrane of the body of a living organism to another neuron, usually through a process referred to as an action potential.
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help me find intersect and slope
Answer:
58.01
Explanation:
because this is he answer to the question 019.10
A family drove 2,275 miles from los angeles to atlanta in a time span of 35 hours. calculate their average speed in miles per hour. what is the avarge speed
The average speed in miles per hour is 65 mph.
Total distance d = 2275 miles
Total time t = 45 hours
To calculate average velocity
v = d/t
where v is velocity, d is distance and t is time.
v = 2275/45
v = 65 mph.
Thus, the average speed in miles per hour is 65 mph.
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What was the kelly-bessemer process used for? reducing the speed for laying rail tracks mass producing train cars monopolizing the iron industry making high-quality steel
The kelly - bessemer process used for converting the iron metal to molten steel by injecting air into molten pig iron.
Molten steel (from an oxygen or electric arc furnace) is poured into a ladle that is brought to the inlet of a continuous casting machine, raised onto a turret, and poured into a tundish. This is a large vessel that ensures the continuous flow of hot metal through a submerged entry nozzle and into a water-cooled and vertical copper mould, where the solidification starts as an outer shell starts encasing a liquid core. Hydrogen is highly soluble in molten steel, including weld metal.
The partial pressure or concentration of hydrogen above the molten steel determines the equilibrium solubility. It is a really difficult process.
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An elephant ran 300 meters in 20 seconds, what was his speed?
Answer: 40 km/hr ( c )
Explanation:
Distance =20 km
Time =30 min=
60
30
hr=
2
1
hr
∴ Speed =
time
Distance
=
(
2
1
hr)
20 km
⇒ Speed =40 km/hr
Option (C) is correct.
derive triangular law or parallelogram law of vectors to find the magnitude of the resultant and direction of two vectors
Two pulses are moving along a string. One pulse is moving to the right and the second is moving to the left. Both pulses reach point P at the same instant.
Since Two pulses are moving along a string, Mu response is Yes, there be an instance in which the wave interference is at the same level as point X because there will be an overlap in the way of the slope of the waves.
What happens when 2 pulses meet?When two pulses collide to produce a bigger pulse, this is called constructive interference. The two beginning pulses' amplitudes are added to create the size of the final pulse.
Note also that if two waves collide while moving across the same medium, wave interference is the result. The medium assumes a shape as a result of the net impact of the two distinct waves on the medium's particles due to wave interference.
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See full question below
Two pulses are moving along a string. One pulse is moving to the right and the second is moving to the left. Both pulses reach point X at the same instant.Will there be an instance in which the wave interference is at the same level as point X?
Metals corrode when left exposed to substances in the environment. State why aluminium quickly becomes protected from further corrosion.
Answer:
Explanation: because it develops a thin oxide layer on the surface when the metal comes in contact with oxygen. The oxide layer protect the aluminum against corrosion and if damaged it will immediately regenerate in presence of
the combined force that you and your friends exert has magnitude 8.00×102n , and starting from rest the car reaches a speed of 1.40 m/s after you have pushed it 5.00 m . find the magnitude of the constant friction force that acts on the car.
The magnitude of the constant frictional force that acts on the car is 574.6
What is frictional force?The frictional force is the force that acts to oppose the relative motion of an object over another.
Friction is a contact force that acts at the surface of contact between two bodies.
The frictional force acting on an object depends on the following:
the coefficient of friction between the surfaces- the coefficient of friction between the two surfaces is a constant ad depends on the nature of the surfaces.the weight of the object moving over another. The greater the weight of the object moving over another surface, the greater the frictional force, and vice versa.The total force exerted by the friends = 800 N
Force on the car as it moves will be = mass * acceleration
acceleration, a = v² - u² / 2 * s
a = 1.40² - 0² / 2 * 5
a = 0.196 m/s²
force = 1.15×10³ kg * 0.196 m/s²
force = 225.4 N
Frictional force = 800 - 225.4
Frictional force = 574.6 N
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Complete question:
A car of mass 1.15×10^3kg is stalled on a horizontal road. You and your friends give the car a constant, forward, horizontal push. There is friction between the car and the road.
the combined force that you and your friends exert has magnitude 8.00×102n , and starting from rest the car reaches a speed of 1.40 m/s after you have pushed it 5.00 m . find the magnitude of the constant friction force that acts on the car.
What electric field e′ would have been required to create a current of 30. 0 amperes in a copper gauge 10 wire with diameter d equal to 0. 259 centimeters?.
The required electric field is 9.58 × 10⁻² N/C
We know that the electric field, E is a product of resistivity and current density
∴ E=jρ ......(i)
Where ρ⇒ Resistivity
j ⇒ Current density
j = I/A
Now, as per the question,
Resistivity of copper, ρ = 1.68 × 10⁻⁸ Ωm
Current, I = 30 ampere
Diameter = 0.259 cm = 0.00259 m
So, Radius, r = Diameter/2
= 1.295 × 10 ⁻⁴m
Now, Cross-sectional area, A = πr²
= 3.14 × (0.001295)²
= 5.26 × 10⁻⁶ m²
Putting the values in equation (i), we get:
[tex]E = 1.68 \times 10^{-8} \times\frac{30}{5.26 \times 10^{-6} }[/tex]
[tex]E= 9.58 \times 10^{-2} N/C[/tex]
Therefore, the required electric field is 9.58 × 10⁻² N/C
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A tray containing 0.20 kg of water at 20 °C is placed in a freezer temperature of the water drops to 0 °C in 10 minutes. (specific heat capacity of water = 4200 J /kg K Calculate
(i) the energy lost by the water as it cools to 0 °C,
(ii) the average rate at which the water is losing energy, in J/s.
Answer:i) Energy lost by the water to cool to a temperature of 0°C from 20°C is 16800 J ii) Average rate at which the water is losing energy = 28J/s when specific heat capacity of water = 4200 J/kg K
Explanation: i)The formula used to calculate the energy lost by the water is
Q=mcΔT where Q= heat or energy lost (or gained), m= mass of the water, c= specific heat capacity of the water, ΔT= [tex]T_{f}-T_{i}[/tex] where [tex]T_{f}[/tex] is the final temperature of the water and [tex]T_{i}[/tex] is the initial temperature of the water
Given, m=0.2kg , c= 4200 J/kg K , [tex]T_{f}=0[/tex]°C and [tex]T_{i}=20[/tex]°C
∴ΔT=[tex]T_{f}-T_{i}=(0-20)[/tex]°C= -20 K ∵Change of temperature in celsius = change of temperature in kelvin
∴[tex]Q=[/tex][tex]0.2*4200*(-20)= -16800 J[/tex] (minus denotes energy loss)
ANS:Energy lost by the water as it cools is Q=16800 joules = 16800J
ii) formula used to calculate average rate at which the water is losing energy is
average rate of losing energy [tex]=\frac{Energy Lost}{Time}[/tex][tex]= \frac{Q}{t}[/tex]
Energy Lost= Q = 16800 J (from answer (i))
Time taken for water to cool to 0°C = t= 10 min= 10*60 sec= 600 sec
∴Avg. rate of losing energy[tex]=\frac{Q}{t}=\frac{16800}{600}=28 J/s[/tex]
ANS: Average rate at which the water is losing energy is 28J/s
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a freight train is traveling due west at 10 miles per hour and begins to slowly pick up speed. of the train reaches a speed of 70 mph in 2 hours, what is the average acceleration of the train.
Answer:
Since 60 mph = 88 ft/sec
10 mph = 14.7 ft/sec
70 mph = 7/6 * 88 ft/sec = 103.7 ft/sec
a = (v2 - v1) / t = (103.7 - 14.7) ft/sec / 7200 sec = .0124 ft/sec^2
q3. a v-tube with angle thetatheta contains some liquid of density ???????? inside and is open to atmosphere at point a. the height of the v-tube is HH. the v-tube can rotate along the axis ab at different speed. assume atmospheric pressure to be PP0. (1) what angular velocity ???????? can cause the pressure at b and c to be equal? (2) find the minimum pressure and its location along bc.
an angled v-tube Theta theta is open to the atmosphere at point a and contains some viscous liquid outside. The v-tube is HH in height. The speed at which the v-tube rotates along axis ab is variable. Assume that PP0 is the atmospheric pressure.
Atmosphere
An atmosphere is a subcaste of gas or layers of feasts that wrap an earth and are held in place by the gravity of the planetary body (from Ancient Greek: "atmós" "vapour," "brume," and "sphaîra" "sphere"). When the graveness is strong and the temperature of the atmosphere is low, the earth keeps its atmosphere. The outer portion of a star, known as its astral atmosphere, is made up of the layers above the opaque photosphere; low-temperature stars may have astral atmospheres that contain emulsion motes.
Nitrogen (78), oxygen (21), argon (0.9), carbon dioxide (0.04), and trace gases make up the Earth's atmosphere.
Most species utilize oxygen for respiration, while shops, algae, and cyanobacteria use carbon dioxide for photosynthesis. Lightning and bacteria use nitrogen obsession to manufacture ammonia, which is used to synthesize nucleotides and amino acids. The atmosphere's stratified structure reduces the dangers of the sun, UV radiation, solar wind, and cosmic shafts to protect species from irreparable harm. The biochemical modification of the pale atmosphere by living beings billions of times has led to the makeup of the Earth's atmosphere as it is now.
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3. Alice and Kai were playing air hockey, which is a game where players hit a puck with paddles so the puck slides across
a table. After the game, they were crashing the puck and two different paddles. The puck was the same in both crashes.
but the paddles were different: the red paddle had less mass, while the purple paddle had more mass. Use the
information in the diagram to answer.
In which crash did the puck experience a stronger force? Why?
Answer: Purple because it is greater than the red in mass and the more mass and the more mass it is the stronger it would be to have a change in velocity.
Explanation:
Answer:
Crash 2
Explanation:
The force on purple paddle was stronger, so the force on the puck has to be stronger
A sample of a gas is in a container. The temperature of the gas is decreased. Based on the relationship between temperature and pressure, what must have happened to the pressure?
If the temperature of the gas is decreased then the pressure will also decrease.
The molecules of a gas receive more energy when heated, causing them to move more quickly. This results in increased pressure and more impacts on the container's walls. On the other hand, cooling the molecules will cause them to slow down and reduce pressure.
This is more explained by Gay Lussac's Law which states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature.
P1/T1 = P2/T2
Thus, with decrease in temperature the pressure will decrease as the move of molecules will be slow now.
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6. If an object's velocity increases from 13.2 m/s to 15.1 m/s in 8.00 seconds, what
is the acceleration of the object?
A. 1.89 m/s²
B. -0.250 m/s²
C. -1.65 m/s²
D. 0.238 m/s²
Answer:
Acceleration 0.238 m/s²
Explanation:
Given:
V₀ = 13.2 m/s
V = 15.1 m/s
t = 8.00 s
__________
a - ?
Is the acceleration of the object:
a = (V - V₀) / t
a = (15.1 - 13.2) / 8.00 ≈ 0.238 m/s²
Acceleration of the object is 0.238 m/s²
What is acceleration?Acceleration of an object is rate of change of velocity with respect to time. Due to having both direction and magnitude, it is a vector quantity of SI unit meter/second².
Given parameters:
Initial velocity; V₀ = 13.2 m/s
Final velocity; V = 15.1 m/s
time; t = 8.00 s
acceleration of the object; a = ?
We know, for accelerated object;
acceleration; a = (V - V₀) / t
⇒a = (15.1 - 13.2) / 8.00 ≈ 0.238 m/s²
Hence, acceleration of the object is 0.238 m/s².
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