Explanation:
|F|= B/2
B/2 = √(A²+B²+2ABcosθ) ------(1)
Since the resultant of A and B is perpendicular to Vector A
tan90°= BSinθ/(A+BCosθ)
(A+BCosθ)=0
Cosθ=-A/B ----(2)
Using equation (1)
B/2 = √(A²+B²+2ABcosθ)
B/2 = √(A²+B²+2AB×-A/B)
B/2=√(A²+B²-2A²)
B/2=√(B²-A²)
B²/4=B²-A²
A²=B²-B²/4
A²=3B²/4
A=√3B/2
Using equation (2)
Cosθ=-A/B
Cosθ=-[√3B/2]/B
Cosθ=-√3/2
θ= cos^-1 (-√3/2)
θ= 150°
What are the conditions necessary for a terrestrial planet to have a strong magnetic field?.
Explain the terms boiling and boiling point.
How is the volume of water affected when it boils at 100°C.?
Don't spam..
The particular temperature at which vaporisation occurs is known as the boiling point of liquid. Volume of water increases when it boils at 100° C. 1 cm3 of water at 100 ° C becomes 1760 cm3 of steam at 100 ° C.
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Hello people ~
The frequency of subsonic sound is
(a) more than 20 Hz
(b) 100 Hz
(c) less than 20 Hz
(d) more than 20,000 Hz
less than 20 Hz
The frequency of subsonic sound is less than 20 Hz
subsonic sound refers to a sound which has a wave that travels slower than the speed of sound.
frequency of audible sound: 20 Hz to 20,000 HzThus subsonic sound < 20 Hz
Answer:
less than 20Hz
Explanation:
Human ears can hear sounds coming in range of 20Hz to 20000Hz or 20kHz.Low or beneath is not audible.Bats can hear below 20Hz ,so they use this to travel in air
Where in their life cycle are stars on the main sequence?.
Answer ,,a main sequence stars burns through the hydrogen in it's core
Explanation:
When the stars go out
Eventually,reaching the end of its life cycle. At this point, it leaves the main sequence. Stars smaller than a quarter the mass of the sun collapse directly into white dwarfs
.
Which object has a constant speed?
a bicycle coming to a stop
a racecar starting a race
a ball falling off a table
a car traveling the speed limit
A regulation 145 g baseball can be hit at speeds of 100 mph. If a line drive is hit essentially horizontally at this speed and is caught by a 65 kg player who has leapt directly upward into the air, what
horizontal speed does he acquire by catching the ball?
This question involves the concept of the law of conservation of momentum.
The horizontal speed acquired by catching the ball will be "0.223 mph".
Law of Conservation of MomentumAccording to the law of conservation of momentum applied in horizontal direction:
Total Initial Momentum = Total Final Momentum
[tex]m_1u_1+m_2u_2=m_1v_1+m_2v_2[/tex]
where,
m₁ = mass of baseball = 145 g = 0.145 kgm₂ = mass of player = 65 kgu₁ = initial horizontal speed of baseball = 100 mphu₂ = initial horizontal speed of player = 0 mphv₁ = final horizontal speed of baseball = 0 mphv₂ = final horizontal speed of player = ?Therefore,
[tex](0.145\ kg)(100\ mph)+(65\ kg)(0\ mph)=(0.145\ kg)(0\ mph)+(65\ kg)(v_2)\\\\v_2=\frac{14.5\ kg.mph}{65\ kg}\\\\[/tex]
v₂ = 0.223 mph
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This is less an answer more like the answers that should be it.
A) 9.9 cm/s
B) 5.6 cm/s
C) 11.8 cm/s
D) 4.2 cm/s
Arm ab has a constant angular velocity of 16 rad/s counterclockwise. At the instant when theta = 60
The linear acceleration of collar D when θ = 60° is - 693.867 inches per square second.
How to determine the angular velocity of a collarIn this question we have a system formed by three elements, the element AB experiments a pure rotation at constant velocity, the element BD has a general plane motion, which is a combination of rotation and traslation, and the ruff experiments a pure translation.
To determine the linear acceleration of the collar ([tex]a_{D}[/tex]), in inches per square second, we need to determine first all linear and angular velocities ([tex]v_{D}[/tex], [tex]\omega_{BD}[/tex]), in inches per second and radians per second, respectively, and later all linear and angular accelerations ([tex]a_{D}[/tex], [tex]\alpha_{BD}[/tex]), the latter in radians per square second.
By definitions of relative velocity and relative acceleration we build the following two systems of linear equations:
Velocities[tex]v_{D} + \omega_{BD}\cdot r_{BD}\cdot \sin \gamma = -\omega_{AB}\cdot r_{AB}\cdot \sin \theta[/tex] (1)
[tex]\omega_{BD}\cdot r_{BD}\cdot \cos \gamma = -\omega_{AB}\cdot r_{AB}\cdot \cos \theta[/tex] (2)
Accelerations[tex]a_{D}+\alpha_{BD}\cdot \sin \gamma = -\omega_{AB}^{2}\cdot r_{AB}\cdot \cos \theta -\alpha_{AB}\cdot r_{AB}\cdot \sin \theta - \omega_{BD}^{2}\cdot r_{BD}\cdot \cos \gamma[/tex] (3)
[tex]-\alpha_{BD}\cdot r_{BD}\cdot \cos \gamma = - \omega_{AB}^{2}\cdot r_{AB}\cdot \sin \theta + \alpha_{AB}\cdot r_{AB}\cdot \cos \theta - \omega_{BD}^{2}\cdot r_{BD}\cdot \sin \gamma[/tex] (4)
If we know that [tex]\theta = 60^{\circ}[/tex], [tex]\gamma = 19.889^{\circ}[/tex], [tex]r_{BD} = 10\,in[/tex], [tex]\omega_{AB} = 16\,\frac{rad}{s}[/tex], [tex]r_{AB} = 3\,in[/tex] and [tex]\alpha_{AB} = 0\,\frac{rad}{s^{2}}[/tex], then the solution of the systems of linear equations are, respectively:
Velocities[tex]v_{D}+3.402\cdot \omega_{BD} = -41.569[/tex] (1)
[tex]9.404\cdot \omega_{BD} = -24[/tex] (2)
[tex]v_{D} = -32.887\,\frac{in}{s}[/tex], [tex]\omega_{BD} = -2.552\,\frac{rad}{s}[/tex]
Accelerations[tex]a_{D}+3.402\cdot \alpha_{BD} = -445.242[/tex] (3)
[tex]-9.404\cdot \alpha_{BD} = -687.264[/tex] (4)
[tex]a_{D} = -693.867\,\frac{in}{s^{2}}[/tex], [tex]\alpha_{BD} = 73.082\,\frac{rad}{s^{2}}[/tex]
The linear acceleration of collar D when θ = 60° is - 693.867 inches per square second. [tex]\blacksquare[/tex]
RemarkThe statement is incomplete and figure is missing, complete form is introduced below:
Arm AB has a constant angular velocity of 16 radians per second counterclockwise. At the instant when θ = 60°, determine the acceleration of collar D.
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a measuring cylinder has a mass of 180g when empty. When a liquid is poured into the cylinder, the level rises to the 95m³ mark. Total mass is now 292g. What is the density of the of the liquid in g/cm³
Answer:
d (density) = m / V = (292 - 180) g / 95 cm^3 = 1.18 g / cm^3
(water is 1 gm / cm^3)
Hello people ~
Voice of man is heavy compared to a woman because
(a) Female vocal cord is longer
(b) Male vocal cord is shorter
(c) Male vocal cord is longer
(d) The concept is not related
Answer:
(c) the male vocal cord is longer
Explanation:
Males have a lower pitch in their voises than females, elongating men's vocal cords.
I am joyous to assist you at any time.
Voice of man is heavy compared to a woman because male vocal cord is longer.
What is the difference between male and female voice?The change is caused by an enlargement in the vocal folds, generating a more serious and adult voice. Generally speaking, the male voice is deeper than the female voice because the vocal muscles grow more in men than in women.
Males have a lower pitch in their voises than females, elongating men's vocal cords.
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What is stated in the 1st Law of Motion?
Answer:
Newton's first law: the law of inertia
Newton's first law states that if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force.
Explanation:
Anything aka if a body is at constant speed in a straight line it would probably remain or keep moving in a straight line unless something slows it down like Fricton.
The _____ acceleration is deceleration
Answer:
hello.
Negative acceleration is also called deceleration.
Explanation:
If the velocity of the object does not change with time, it has zero acceleration.
A rollercoaster loop has a radius of 22.7 m. what is the minimum speed the coaster must have at the top of the loop to not fall off the track? (unit = m/s)
Answer:
v = 14.92 m/s
Explanation:
First, make a free body diagram and see the forces in the y-direction.
∑F_y = F_N - F_gUse Newton's 2nd Law F = ma to replace ∑F_y with m * a_y.
m * a_y = F_N - F_gThe acceleration in the y-direction is the centripetal acceleration, a_c = v^2/r.
m * v^2/r = F_N - mgThe normal force is 0 because this is where the rollercoaster is not falling off the track yet not touching the track.
m * v^2/r = - mgThe masses cancel out.
v^2/r = -gSolve for v to find the speed of the rollercoaster at the top of the loop.
v^2 = -(-9.81) * r v = √(9.81 * 22.7)v = 14.9227The minimum speed the coaster must have at the top of the loop to not fall off the track is 14.92 m/s.
A distant astronomical object (a quasar) is moving away from us at half the speed of light. what is the speed of the light we receive from this quasar?
For a distant astronomical object (a quasar) is moving away from us at half the speed of light, the speed of the light we receive from this quasar is mathematically given as c = 3x108 m/s
What is the speed of light?Generally, the equation for the is mathematically given as
The speed of light can be said to be measured to be approximately the value c = 3x108 m/s
.
In conclusion, An will not influence 3x108 m/s unless both are inertia and frames refrences where newtons laws are valid, so the speed of light measured from the earth frame is equal to 3x108 m/s
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help me with this question ^^
An electroscope is a device which is used to find if an object is
(a) charged
(b) magnetic
(c) free of cracks
(d) hot
Answer:
Charged
Explanation:
Look at a example below
You took a pen Rubbed it on your hair fastly for 2 mins If you took that rubbed part towards paper ,both will be attracted and joined for some while.PLEASE HELP!!!
With upward speeds of 12.5 m/s, the elevators in the Yokohama Landmark Tower in Yokohama, Japan, are among the fastest elevators in the world. Suppose a passenger with a mass of 70.0 kg enters one of these elevators. The elevator then goes up, reaching full speed in 4.00 s. Calculate the net force that is applied to the passenger during the elevator's acceleration.
The net force that is applied to the passenger during the elevator acceleration is 218.75 N.
What is net force?This is the single force obtained from the combinatiion of two or more forces
To calculate the net force that is applied to the passenger during the elevator's acceleration, we use the formula below.
Formula:
F = m(v-u)/t............ Equation 1Where:
F = forcem = massv = Final velocityu = initial velocityt = time.From the question,
Given:
m = 70 kgu = 0 m/sv = 12.5 m/st = 4 sSubstitute these values into equation 1
F = 70(12.5-0)/4F = 218.75 NHence, The net force that is applied to the passenger during the elevator acceleration is 218.75 N.
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If a 5-kg object experiences a 10-N force for a duration of 0. 10-second then what is the impulse exerted by the force on the object? What is the momentum change of the object? What is the change in velocity for the object?
Answer:
orce = rate of change of momentum which is m a if the mass is constant
10 Newtons = change of momentum/0.10 second
so change of momentum = 1 kg m/s
by the way the change in speed would be 1/5 = .2 m/s
Explanation:
If a 5-kg object experiences a 10-N force for a duration of 0. 10-second then the impulse exerted by the force on the object would be 1 Ns, and the change in the momentum would be 1 Ns.
What is momentum?It can be defined as the product of the mass and the speed of the particle, it represents the combined effect of mass and the speed of any particle, and the momentum of any particle is expressed in Kg m/s unit.
As given in the problem If a 5-kg object experiences a 10-N force for a duration of 0. 10-second then we have to find out what the impulse exerted by the force on the object.
P = force × time
= 10 × 0.1
= 1 Ns
Thus, If a 5-kg object experiences a 10-N force for a duration of 0. 10-second then the impulse exerted by the force on the object would be 1 Ns, and the change in the momentum would be 1 Ns.
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Two objects of the same mass travel in the same direction along a horizontal surface. Object X
has a speed of 5 ms
and object Y
has a speed of 2 ms
, as shown in the figure. After a period of time, object X
collides with object Y
.
Consider the situation in which the objects collide but do not stick together. Which of the following predictions is true about the center of mass of the two-object system immediately after the collision?
After the collision, object X will move at a speed of 2 m/s in its original direction while object Y will move at a speed of 5 m/s in its original direction.
Elastic collision of the two objectsWhen the two objects collide but do not stick together, the type of collision is elastic collision.
In elastic collision, both momentum and kinetic energy are conserved.
Final velocity of the two objects after collsionmu₁ + mu₂ = mv₁ + mv₂
5m + 2m = mv₁ + mv₂
m(5 + 2) = m(v₁ + v₂)
7 = v₁ + v₂ -------- (1)
Apply the concept of one direction velocity;
u₁ + v₁ = u₂ + v₂
5 + v₁ = 2 + v₂
v₂ = v₁ + 3 ------ (2)
Solve (1) and (2) together;
7 = v₁ + v₁ + 3
4 = 2v₁
v₁ = 2 m/s
v₂ = 2 + 3 = 5 m/s
Thus, after the collision, object X will move at a speed of 2 m/s in its original direction while object Y will move at a speed of 5 m/s in its original direction.
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Which letter explains why no machine is 100 percent efficient.
A.Mechanical energy is transformed into thermal energy by friction.
B.Mechanical energy is transformed into electrical energy by a spark.
C.Thermal energy is transformed into mechanical energy by friction.
Answer:
A
Explanation:
Think about rubbing your hands together- the friciton produces heat
what is the result of ocean acidification
Answer:
Ocean acidification reduces the amount of carbonate, a key building block in seawater. This makes it more difficult for marine organisms, such as coral and some plankton, to form their shells and skeletons, and existing shells may begin to dissolve.
Answer:
The intake of carbon dioxide (CO2) from the atmosphere causes ocean acidification, which is the continual decline in the pH value of the Earth's oceans. The burning of fossil fuels by humans is the primary cause of ocean acidification. The amount of carbon dioxide absorbed by the ocean grows in lockstep with the amount of carbon dioxide in the atmosphere. This causes a sequence of chemical reactions in the seawater, which has a negative impact on the, however, their rine life that lives beneath the surface. Carbonic acid is formed when carbon dioxide dissolves in seawater (H2CO3). The pH value of the ocean surface is estimated to have decreased from approximately 8.25 to 8.14 between 1751 and 1996, representing a nearly 30% increase in H+ ion concentration in the world's oceans (note that the pH scale is logarithmic, so a change of one pH unit equals a tenfold change in H+ ion concentration). The pH of the ocean in 2020 will be 8.1, according to the National Oceanic and Atmospheric Administration.
Explanation:
Red light has a wavelength of (7. 21x10^7)m. What is the frequency of this light?
Answer:
TO answer this question i need wave speed
Explanation:
A 10. 0 cm object is 5. 0 cm from a concave mirror that has a focal length of 12 cm. What is the distance between the image and the mirror? 3. 5 cm –3. 5 cm 8. 6 cm –8. 6 cm.
The distance between the image and the mirror is -8.6 cm
What is concave mirror?A concave mirror has a reflective surface that is curved inward and away from the light source. Concave mirrors reflect light inward to one focal point.
Unlike convex mirrors, the image formed by a concave mirror shows different image types depending on the distance between the object and the mirror.
Let's use the mirror equation to solve the problem:
[tex]\dfrac{1}{f}=\dfrac{1}{d_o}+\dfrac{1}{d_i}[/tex]
where f is the focal length of the mirror, the distance of the object from the mirror, and the distance of the image from the mirror.
For a concave mirror, for the sign convention f is considered to be positive. So we can solve the equation for by using the numbers given in the text of the problem:
[tex]\dfrac{1}{12}=\dfrac{1}{5}+\dfrac{1}{d_i}[/tex]
[tex]\dfrac{1}{d_i}=-\dfrac{7}{60}[/tex]
[tex]d_i=-8.6\ cm[/tex]
Where the negative sign means that the image is virtual, so it is located behind the mirror, at 8.6 cm from the center of the mirror.
Hence the distance between the image and the mirror is -8.6 cm
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Scientists observed a rocky, rotating object orbiting in space. It was 250 km wide. The rocky object was located several times farther away from the sun than the earth
The rocky object orbiting in space is most likely referred to as an asteroid.
What is an Asteroid?This is referred to a rocky object which revolve around the sun and are considered too small to be called a planet.
Asteroids was observed with the use of a telescope and is around 250 km wide thereby making it the most appropriate choice.
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A student watches the tide change, and sees water waves pass the end of the dock
that follow the pattern shown below:
13)
The student counts the waves with a stopwatch, and determines that it takes 8.75
seconds for a single wave to go by. The wave frequency is ----
The frequency of the wave at the given period is 0.114 Hz. This frequency shows the number of revolution of the wave in a second.
What is frequency of a wave?The frequency of a wave is the number of revolutions of the wave per second.
Frequency of a wave is determined by taking the inverse of period of the wave.
The frequency of the wave at the given period is calculated as follows;
f = 1/T
Where;
f is the frequencyT is period of the wavef = 1/8.75
f = 0.114 Hz
Thus, the frequency of the wave at the given period is 0.114 Hz.
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The cooper family hijacks a UAV (Unmanned Aerial Vehicle). What do you know about UAVs and how they are used today?
Interstellar movie☝️
Interstellar is a movie about the human race being faced with a
civilization ending blight. A small group of brave individuals explore
possible new habitable worlds for humans. The following questions
will help guide you through the movie and hopefully get you
thinking about the future.
1. The Cooper family hijacks a UAV (Unmanned Aerial Vehicle).
What do you know about UAVs and how they are used today?
2. While at the parent-teacher conference, Murphy’s teacher
mentions that the Apollo program -- the same program that
landed humans on the Moon -- was just propaganda to
convince the Soviet Union to bankrupt themselves trying to do
the same. The reason for this was to encourage children to
take care of their own planet, rather than wasting precious
resources day dreaming of leaving it. Which side of the fence
would you sit on? Would you look for ways to save Earth and
our ability to stay there, or would you look to the sky, and find
a new planet to live on? Why?
3. A) What natural disaster(s) is Earth suffering from in the beginning of Interstellar?
B) If one of these happened now what actions would you take to protect yourself?
4. Cooper, Doyle, Romilly, and Dr. Brand (female) rendezvous with the Endurance in orbit around Earth. Once
onboard, they begin to spin the Endurance. Why? (Think about the physics happening here!) Draw a diagram.
5. Why or why isn’t space exploration important for the people in the movie interstellar? Why or why isn’t
space exploration important in today’s society? Defend your answers.
6. Explain time dilation as best as you can.
7. A) Estimate how long Dr. Mann went without human contact while on the ice planet:
The Lazarus mission was __________ years ago. It takes _______ years to get to Saturn from Earth. Cooper
and Dr. Brand were on Miller’s planet for approximately __________ years. This means the total time Dr.
Mann went without human contact is: ___________ years.
B) Consider the longest time away from human contact you've experienced. What did you do to keep yourself
occupied?
Useful Vocabulary
Blight: A specific symptom affecting plants in
response to infection by a pathogenic organism. The
potato famine of Ireland was caused by blight.
Event horizon: Is a point in which not even light can
escape the gravitational influence of the black hole.
Maroon: The intentional action of leaving someone
in a remote area such as an inhabitable island.
Rendezvous: When two objects meet and typically
dock together while in space.
Time dilation: A difference of elapsed time between
two events as measured by observers either moving
relative to each other or differently situated from
gravitational masses.
UAV: Unmanned Aerial Vehicles are remote
controlled or autonomous flying vehicles.
Unmanned aerial vehicles (UAVs) are typically used for a variety of purposes such as:
Monitoring and surveillance.Remote sensingPhotographyDisaster responseWhat is an unmanned aerial vehicle?An unmanned aerial vehicle (UAV) is also referred to as a drone and it can be defined as an aircraft that is designed and developed to be piloted or controlled by a remote control (ground-based controller) and on-board computer systems.
This ultimately implies that, an unmanned aerial vehicle (UAV) is a class of aircrafts that can fly without any human pilot, cabin crew, or passengers on board.
In conclusion, unmanned aerial vehicles (UAVs) carries no human pilot and are typically used for a variety of purposes such as:
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What is the average velocity of the fly between 0 and 15 seconds
Answer:
where is the displacement
[tex]v = \frac{s}{t} [/tex]
The average velocity of the fly between 0 and 15 seconds will be 10 m/sec.Velocity is the time-based component.
What is average velocity?
The average velocity is the ratio of the total distance traveled to the total time taken by the body. Its unit is m/sec.
From the given graph it is obsderved that the displacement from 0 to 15 seconds will be 150 m.
[tex]\rm V = \frac{D_2-d_1 }{t_2-t_1} \\\\ V = \frac{150}{15-0} \\\\ V= 10 \ m/sec[/tex]
Hence the average velocity of the fly between 0 and 15 seconds will be 10 m/sec.
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What is the wavelength of a light ray that has a frequency of 7.4 E12 Hz?
The wavelength of the light ray with the given frequency is 4.05 × 10⁴nm.
Given the data in the question;
Frequency of the light ray; [tex]f = 7.4 * 10^{12}Hz[/tex]Wavelength; [tex]\lambda = \ ?[/tex]WavelengthWavelength can be simply defined as the spatial period of a periodic wave. When the shapes of waves are repeated, the distance over which they are repeated is called wavelength. Wavelength is expressed as;
[tex]\lambda = \frac{c}{f}[/tex]
Where [tex]\lambda[/tex] is wavelength, f is frequency and c is speed of light( [tex]c = 3*10^8m/s[/tex] )
We substitute our values into the expression above to determine the wavelength of the light ray.
[tex]\lambda = \frac{c}{f} \\\\\lambda = \frac{3*10^8m/s}{7.4*10^{12}s^{-1}}} \\\\\lambda = \frac{3*10^8ms/s}{7.4*10^{12}}}\\\\\lambda = 4.05*10^{-5}m\\\\\lambda = 4.05*10^{4}nm[/tex]
Therefore, the wavelength of the light ray with the given frequency is 4.05 × 10⁴nm.
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I will be giving the brainliest to whoever.What is the PERCENT efficiency if a computer is supplied with 500 J of energy and is able to convert 400 J to useful energy?
A. 0.8 %
B. 8 %
C. 80 %
D. 800 %
What is atmospheric pressure?
Who discovered the basic laws of planetary orbits?.
Answer:
Johannes Kepler
A 50 kg object moving at 15 m/s collides with another 50 kg object moving in the same direction at 10 m/s. If the collision is inelastic, what is the final velocity of the two objects after they combine?
Answer:
12.5 m/s
Explanation:
By conservation of momentum, we have that:
[tex]\displaystyle m_1v_1 + m_2v_2 = m_1v_1' + m_2v_2'[/tex]
Because the two objects combine after collision, they will have the same velocity:
[tex]\displaystyle m_1v_1 + m_2v_2 = (m_1+m_2)v_f[/tex]
Substitute and solve for final velocity:
[tex]\displaystyle \begin{aligned} (50 \text{ kg})(15\text{ m/s}) + (50\text{ kg})(10\text{ m/s}) & = ((50+50)\text{ kg})v_f \\ \\ v_f & = 12.5\text{ m/s}\end{aligned}[/tex]
In conclusion, the final velocity of the system will be 12.5 m/s.