The object must be placed 39 cm in front of the concave mirror to create an upright image three times the height of the object.
Assuming the object is located outside the focal point of the concave mirror,
1/f = 1/o + 1/i
where f is the focal length, o is the object distance, and i is the image distance. For a concave mirror, the focal length is negative and equal to half the radius of curvature:
f = -R/2 = -39/2 = -19.5 cm
We also know that the magnification is given by:
m = -i/o
where the negative sign indicates that the image is inverted.
We are given that the height of the image is three times the height of the object, so:
m = i/o = -3
Solving for i in terms of o and substituting into the mirror equation,
1/-19.5 = 1/o - 3/o
Simplifying, we get:
-1/19.5 = -2/o
Solving for o, we get:
o = -39 cm
Since the object distance must be positive, we take the absolute value of the result,
o = 39 cm
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You decide to use an iron-titanium alloy for a new turbine engine. The melting temperature of iron is 1538°C and the melting temperature of titanium is 1668°C. Do you think it will be safe to have the turbine component operate at 1150°C?
Yes, it will be safe to have the turbine component operate at 1150°C
Based on the given information, the melting temperatures of iron and titanium are 1538°C and 1668°C, respectively. In an iron-titanium alloy, these two elements are combined, resulting in an intermediate melting temperature. This alloy would have a higher melting temperature than pure iron and lower than pure titanium.
Operating the turbine engine at 1150°C would be safe, as this temperature is significantly below the melting temperatures of both elements. It provides a sufficient margin of safety for the alloy, ensuring that it remains solid and stable during operation. Additionally, alloys typically have improved mechanical properties, such as increased strength and resistance to wear, compared to their constituent elements. This makes iron-titanium alloys suitable for high-temperature applications like turbine engines.
In summary, using an iron-titanium alloy for a turbine engine operating at 1150°C should be safe and appropriate due to its enhanced mechanical properties and melting temperature range.
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What is the frequency of a photon that is emitted when the dipole moment of a proton flips in a magnetic field of 2.5 T? The energy of a photon is related to its frequency by the equationLaTeX: E=hf, whereLaTeX: fis the frequency and h=6.626×10−34J⋅s is Planck's constant. Provide your answer in megahertz (= 106 Hz). Again, the dipole moment of a proton is 1.41x10-26 Am2.
The frequency of the photon emitted when the dipole moment of a proton flips in a magnetic field of 2.5 T is approximately 53.5 MHz.
How to find the frequency of the photon?To find the frequency of the photon emitted when the dipole moment of a proton flips in a magnetic field, we can use the equation:
E = hf
where E is the energy of the photon, h is Planck's constant (6.626 × 10⁻³⁴ J·s), and f is the frequency of the photon.
We know that the energy of the photon is related to the dipole moment of the proton by:
E = μB
where μ is the dipole moment of the proton (1.41 × 10⁻²⁶ Am²) and B is the magnetic field (2.5 T).
Substituting the values into the equation, we have:
μB = hf
Solving for f, we get:
f = (μB) / h
Plugging in the values, we have:
f = (1.41 × 10⁻²⁶ Am² * 2.5 T) / (6.626 × 10⁻³⁴ J·s)
Calculating the value, we find:
f ≈ 5.35 × 10¹³ Hz
To convert the frequency to megahertz (MHz), we divide by 10⁶:
f ≈ 53.5 MHz
Therefore, the frequency of the photon emitted when the dipole moment of a proton flips in a magnetic field of 2.5 T is approximately 53.5 MHz.
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You do 20 J of work pushing a crate up a ramp. If the output work from the inclined plane is 11 J, then what is the efficiency of the inclined plane?
Answer:
55%
Explanation:
take efficiency=power output/power input multiply by 100%
a body is thrown vertically upward from the earth's surface and it took 8 seconds to return to its original position . find out the initial velocity with which it was thrown up
Answer:
The initial velocity with which the body was thrown up is 39.2 m/s
Explanation:
The given parameters for the body are;
The time it takes the body to return back to its initial position = 8 seconds
To answer the question, we make use of the kinematic equation of motion, v = u - g·t
Where
v = The final velocity of the body = 0 m/s at the maximum height
u = The initial velocity
g = The acceleration due to gravity = 9.8 m/s²
t = The time in which the body spends in the air
Therefore, at maximum height, we have;
v = 0 = u - g·t
u = g·t
t = u/g
From h = 1/2gt², which gives t = √(2·h/g), the time the body takes to maximum height = The time the body takes to return to its original position from maximum height.
Therefore, the total time in which the body is in the air = 2 × t = 2× u/g
∴
The total time in which the body is in the air = The time it takes the body to return back to its initial position after being thrown = 2 × t = 8 seconds
∴ 2 × t = 8 s = 2 × u/g
8 s = 2 × u/g
u = (8 s × g)/2
∴ u = (8 s × 9.8 m/s²)/2 = 39.2 m/s
The initial velocity with which the body was thrown up = u = 39.2 m/s.
For the velocity-time graph shown, which statement describes what happens to the velocity between approximately 24 s and 25 s?
A) The lander's velocity increases away from the reference.
B) The lander's velocity decreases toward the reference.
C) The lander's velocity decreases away from the reference.
D) The lander's velocity increases toward the reference.
The statement that describes what happens in the graph is option (B).
The lander's velocity decreases toward the reference.
What is velocity time graph?Velocity time graph is a type of graph that describes the change in velocity with respect to time of motion of an object.
Below is the basic explanation of the behavior of the average velocity of the particle with time.
initially at 10 seconds, the average velocity of the particle was constant.above 10 seconds, the average velocity of the particle increases with increase in time of motion.above 15 seconds, the increase in the average velocity with time decreased. between 20 and 25 seconds, there was a decrease in the average velocity from about - 5 m/s to about -15 m/s.Thus, we can conclude that between 20 and 25 seconds in the velocity tike graph, the average velocity of the object decreased towards the reference point (reference velocity = - 40 m/s.).
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Momentum:
3
Mass A has a mass of 10 kg while mass B has a mass of 20
kg. Which of these must be true?
Answer:
D
Explanation:
F=ma
a=F/m
according to option D, F is constant
so acceleration is inversely proportional to mass and A has half the mass of B. Hence, acceleration of A will be twice of B if same force is applied.
A gasoline engine takes in 1. 61 10 J of heat and delivers 3700 J of work per cycle. The heat is obtained by burning gasoline with a heat of combustion of 4. 60 10 J/g. (a) What is the thermal efficiency? (b) How much heat is discarded in each cycle? (c) What mass of fuel is burned in each cycle? (d) If the engine goes through 60. 0 cycles per second, what is its power output in kilowatts? In horsepower?
(a). The thermal efficiency is approximately 22.9%.
(b). The heat discarded in each cycle is approximately 1.6063 × \(10^6\) J.
(c). The mass of fuel burned in each cycle is approximately 0.035 kg.
(d). The engine's power output is approximately 222 kW or 297.6 hp.
To solve this problem, let's use the following formulas and conversions:
Thermal efficiency (η) = (Useful work output / Heat input) * 100%Heat input = Heat of combustion * Mass of fuel burnedPower output (P) = Work done per cycle * Number of cycles per second1 kilowatt (kW) = 1000 watts (W)1 horsepower (hp) = 745.7 watts (W)Given:
Heat input (Qin) = 1.61 × \(10^6\)J
Work done per cycle (W) = 3700 J
Heat of combustion of gasoline (H) = 4.60 × \(10^7\) J/kg
Cycles per second (f) = 60.0 cycles/s
(a) To calculate the thermal efficiency:
Thermal efficiency (η) = (Useful work output / Heat input) * 100%
η = (W / Qin) * 100%
η = (3700 J / 1.61 × 10^6 J) * 100%
η ≈ 0.229 * 100%
η ≈ 22.9%
(b) To calculate the heat discarded in each cycle:
Heat discarded = Heat input - Useful work output
Heat discarded = Qin - W
Heat discarded = 1.61 × \(10^6\) J - 3700 J
Heat discarded ≈ 1.6063 × \(10^6\) J
(c) To calculate the mass of fuel burned in each cycle:
Heat input = Heat of combustion * Mass of fuel burned
Mass of fuel burned = Heat input / Heat of combustion
Mass of fuel burned = 1.61 × \(10^6\) J / 4.60 × \(10^7\) J/kg
Mass of fuel burned ≈ 0.035 kg
(d) To calculate the power output in kilowatts and horsepower:
Power output (P) = Work done per cycle * Number of cycles per second
P = W * f
P = 3700 J * 60.0 cycles/s
P = 2.22 × \(10^5\) J/s
Power output in kilowatts:
P(kW) = P / 1000
P(kW) ≈ 2.22 × \(10^5\) J/s / 1000
P(kW) ≈ 222 kW
Power output in horsepower:
P(hp) = P / 745.7
P(hp) ≈ 2.22 × \(10^5\) J/s / 745.7
P(hp) ≈ 297.6 hp
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A heat engine absorbs 30 000 J of heat and releases 15 000 J of heat per cycle. Pa-help po
A heat engine is a device that converts heat energy into mechanical work. In each cycle, the engine absorbs 30 000 J of heat and releases 15 000 J of heat.
This means that the engine is only able to convert a portion of the heat it absorbs into useful work. The remaining heat is released into the surrounding environment. The efficiency of a heat engine is defined as the ratio of the useful work output to the heat input. In this case, the efficiency of the engine would be 15 000 J/30 000 J or 0.5, which means that the engine is only able to convert 50% of the heat it absorbs into useful work. In order to improve the efficiency of a heat engine, engineers must work to reduce the amount of heat that is lost to the environment during each cycle. This can be done through improvements in the design of the engine, such as increasing the temperature difference between the hot and cold sides of the engine or reducing the amount of friction and resistance within the engine itself.
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How many minutes does it take for light to go from the sun to the planet Uranus, a distance of 2.88x109 km? (The
velocity of light is constant in free space and is 3.00x108 m/s)
Answer:
t = 160 minutes
Explanation:
Given that,
Distance of Uranus from Sun is \(2.88\times 10^9\ km\)
We need to find the time taken by the light to go from sun to Uranus if the velocity of light is constant in free space and it is equal to c.
So,
\(t=\dfrac{d}{v}\\\\t=\dfrac{2.88\times 10^9\times 10^3\ m}{3\times 10^8}\\\\t=9600\ s\)
Since, 1 minute = 60 seconds
t = 160 minutes
So, 160 minutes is taken by the light.
EASY QUESTIONS! DUE IN 15 MIN WILL MARK BRAINLIEST.
1. What is the sum of a vector 8 m south and a vector 12 m north? *
2. What is the sum of a vector 12 m north and a vector 8 m north? *
PLEASE SHOW WORK AND EXPLAIN
Explanation:
As they are in same direction, you can add them directly. And result is 12 + 8 m = 20 m North. If you use vector addition: Vectors = 12m & 8 m & angle b/w them is 0°(as both are in same direction).
How would you expect Newton’s Cradle to behave on a large planet such as Jupiter?
Claim:
Evidence:
Reasoning:
The cradle behaves different due to higher force of gravity.
The Newton’s Cradle behave differently on a large planet such as Jupiter because of the higher gravitational force as compared to the earth. We know that the ball in the cradle that we moves upward comes back to hit the other ball due to force of gravity so if the gravity is increased than the ball on the other end did not move on a certain height due to strong force of attraction and may be the motion of the Newton’s Cradle stops or very slow. The gravity of Jupiter is 2.4 times higher than earth.
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which direction should a ceiling fan turn in the summer
Two forces of magnitude 6Newton and 10Newton are inclined at an angle of 60 degree with each other. Calculate the magnitude of the resultant and the angle made by the force with 60Newton force.
The resultant force is 8.7 N and the angle formed is 59 degrees
What is the resultant force?The adjacent sides drawn from a point can be used to depict the magnitude and direction of two vectors acting simultaneously at a point.
We can see that the vectors can be shown by the sides of the parallelogram as is clear in the image.
We have the resultant force as;
R^2 = 6^2 + 10^2 - 2(6 * 10)Cos 60
R = √ 6^2 + 10^2 - 2(6 * 10)Cos 60
R = √ 36 + 100 - 2(60)cos 60
R = 8.7 N
The angle made is tan-1 (10/6)
= 59 degrees
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A circuit has an impedance of 5 ohms and a voltage of 100 volts. What is the current flow?
A circuit with an impedance of 5 ohms and a voltage of 100 volts has a current flow of 20 A.
The expression of an electronic component, circuit, or system's resistance to alternating and/or direct electric current is called impedance, indicated by the letter Z. Resistance and reactance are two distinct scalar (one-dimensional) phenomena that combine to form impedance, a vector (two-dimensional) variable.
\(Z^{}\) = \(\frac{V}{I}\)
(for a pure resistor where Z=R,preserving the form of the DC Ohm's law).
\(I=\frac{V}{Z}\)
\(I = \frac{100}{5}\)
I = 20 A
Therefore, A circuit with an impedance of 5 ohms and a voltage of 100 volts has a current flow of 20 A.
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What happens to the brightness of lightbulbs if you add them to each circuit?
Adding bulbs to a series will make them dimmer because current is reduced, adding bulbs to a parallel will make them brighter because the current through each individual bulb goes up.
Adding bulbs to a series will make them brighter because each bulb will take more current, adding bulbs to a parallel will not affect the brightness because the current through each individual bulb remains the same.
Adding bulbs to a series will make them dimmer because current is reduced, adding bulbs to a parallel will not affect the brightness because the current through each individual bulb remains the same.
Adding bulbs to a series will make them brighter because current is increased, adding bulbs to a parallel will make them dimmer because the current has to be split up between them.
Adding bulbs into a series will make them dimmer because the current is decreased, adding bulbs to a parallel will not affect the brightness because the current through each individual bulb remains the same.
Therefore, Option (C) is correct.
What are series circuits and parallel circuits?A series circuit is one where the same current flows through all the components in the circuit. The current has only one path in series circuits. A parallel circuit is one where the electric current has multiple paths to flow through. The components of the parallel circuits will have the same voltage across all ends.
When we connect bulbs in the circuit where all are connected in series then the net resistance of the circuit will increase and the voltage across each bulb will decrease.
Since voltage decreases across each bulb then the current across each bulb will decrease and the bulb gets dimmer because the current is reduced.
When we connect bulbs in parallel the voltage and current across each bulb will remain the same and then adding bulbs to a parallel will not affect the brightness.
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4 answers. Anyone know?
Answer:
lift
weight
thrust
air resistance
Explanation:
plz mark me as brainliest
Answer: Upthrust, lift, air resistance, and thrust
Explanation:
All of these 4 elements are taken into account during the design and creation of a plane.
If a long-distance runner runs at an average speed of 12 mph for 4.5 hours, how much distance will they have covered?
Answer:
54 miles.
Explanation:
12 times 4.5.
Answer:
\(\boxed {\tt 54 \ miles}\)
Explanation:
Distance can be found by multiplying the speed by the time.
\(d=s*t\)
The speed is 12 miles per hour and the time is 4.5 hours. Therefore,
\(s= 12 \ mi/hr\\t=4.5 \ hr\)
Substitute the values into the formula.
\(d= 12 \ mi/hr * 4.5 \ hr\)
Multiply. Note that that hours, or "hr" will cancel each other out.
\(d= 12 \ mi * 4.5\)
\(d= 54 \ mi\)
d= 54 miles
The distance covered is 54 miles.
What is the wavelength of a sound wave if the air is 20 degrees Celsius, and the frequency is 100 Hz?
Question 9 options:
41. 16 m
3. 52 m
None of these.
3. 43 m
2000 m
The wavelength of a sound wave at 20 degrees Celsius and a frequency of 100 Hz is approximately 3.4 meters.
Sound waves are mechanical waves, which means they require a medium to propagate. In the case of sound waves, this medium is usually air. The speed of sound in air depends on various factors, including temperature, humidity, and pressure. At 20 degrees Celsius, the speed of sound in air is approximately 343 meters per second.
The wavelength of a sound wave is defined as the distance between two successive points in the wave that are in phase, or the distance over which the wave repeats itself.
It is determined by dividing the speed of sound by the frequency of the wave, using the formula λ = v/f, where λ is the wavelength, v is the speed of sound, and f is the frequency of the wave.
Substituting the values of v and f given in the question, we get λ = 343/100, which simplifies to approximately 3.4 meters. Therefore, the wavelength of the sound wave in this scenario is approximately 3.4 meters.
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What information about elements can be collected from the periodic table?
Answer:
Using the data in the table scientists, students, and others that are familiar with the periodic table can extract information concerning individual elements. For instance, a scientist can use carbon's atomic mass to determine how many carbon atoms there are in a 1 kilogram block of carbon.
Explanation:
HOPE THIS HELPS LIKE AN RATE PLZ
Answer:
Within each element square, information on the element's symbol, atomic number, atomic mass, electronegativity, electron configuration, and valence numbers can be found. At the bottom of the periodic table is a two row block of elements that contain the lanthanoids and actinides.
Explanation:
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. a diverging lens has a focal length that has a magnitude of 33.0 cm. an object is placed 21.0 cm in front of this lens. calculate the magnification.
A diverging lens has a focal length that has a magnitude of 33.0 cm. an object is placed 21.0 cm in front of this lens. The magnification will be -12.833 cm
diverging lens = concave lens
focal length = - 33 cm
u = - 21 cm
magnification = image distance / object distance
using lens formula
1/v - 1/u = 1/f
1/v = 1/f + 1/u
= 1/-33 -1/21
v = -12.833 cm
A diverging lens has a focal length that has a magnitude of 33.0 cm. an object is placed 21.0 cm in front of this lens. The magnification will be -12.833 cm
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A car driving down the road runs out of gasoline. Which of Newton’s laws explains why the car continues to move without gasoline?
Answer:
because the car needs gas so why wouldnt it stop working
Explanation:
32. If a ball is given a push so that it has an initial velocity of 2 m/s down a certain inclined plane, then the distance it has rolled after t seconds is s = 2t + t2. How long does it take for the velocity to reach 24 m/s? (a) 2 seconds (b) 4 seconds (c) 5 seconds (d) 11 seconds (e) 12 seconds
If a ball is given a push so that it has an initial velocity of 2 m/s down a certain inclined plane, then the distance it has rolled after t seconds is s = 2t + t². Then it takes 11 seconds for the velocity to reach 24 m/s. The correct option is D.
To find the time it takes for the velocity of the ball to reach 24 m/s, we need to solve for the time when the velocity function equals 24 m/s.
The velocity function is the derivative of the distance function, so we'll first find the derivative of the distance function s = 2t + t² with respect to time t:
ds/dt = d/dt(2t + t²)
ds/dt = 2 + 2t
Now we can set the velocity function equal to 24 m/s and solve for t:
2 + 2t = 24
Subtracting 2 from both sides:
2t = 22
Dividing both sides by 2:
t = 11
Therefore, it takes 11 seconds for the velocity to reach 24 m/s.
The correct answer is (d) 11 seconds.
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What happened to the maximum height of consecutive swings
Answer:
we need more info
Explanation:
Plz help me
Thank you so much
Answer:
I believe its the blue, sorry if I'm wrong
A sound wave has a speed of 342 m/s and a wavelength of 2.15 meters. What is the frequency of this wave?
A. 159 hertz
B. 127 hertz
C. 239 hertz
D. 278 hertz
The frequency of this sound wave is 159 hertz. Hence, correct answer is option A.
Type of mechanical wave that propagates through a medium, such as air, water, or solids, as vibrations is called sound wave and they are produced when object vibrates, creating disturbances in the surrounding medium. These disturbances cause the particles of the medium to oscillate back and forth and transmitting energy from the source of the sound to surrounding areas.
The formula to calculate the frequency of a sound wave is: frequency = speed of sound/wavelength. In this case, the speed of the sound wave is given as 342 m/s and the wavelength is given as 2.15 meters. So, the frequency can be calculated as:
frequency = 342 m/s / 2.15 meters
frequency = 159.07 hertz
Therefore, the correct answer is A. 159 hertz.
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An object of mass m attached to spring with constant k oscillates with amplitude Assuming air resistance and the mass of the spring to be negligible; which of the following changes alone would cause the period of this oscillation to increase? Increasing m Il; Increasing A III: Using spring with greater k Lonly Submit Il only Ior IIl only Il or IIl only V, Il or III
The only option II, increasing the mass, would increase the period of the oscillation.
The period of oscillation is defined as the time required for a single oscillation to occur. It is determined by the square root of the mass attached to the spring divided by the spring constant.
The formula for the period is:
T = 2π√m/k
Where T is the period, m is the mass, and k is the spring constant. Therefore, an increase in mass or a decrease in spring constant k would lead to an increase in the period of the oscillation. Only option II would result in an increase in the period of the oscillation.
The period of oscillation is a function of the mass of the object and the spring constant. If the mass is increased, the period of oscillation increases, and if the spring constant is increased, the period of oscillation decreases. It is also unaffected by the amplitude or air resistance. Thus, only option II, increasing the mass, would increase the period of the oscillation.
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What does the evidence in this passage suggest?
A.
Julia and her husband lack an understanding.
B.
Miranda dislikes helping her mother in the kitchen.
C.
The father is indifferent to Miranda and Julia.
D.
Miranda has yet to warm up to her step-father.
Answer: D
Explanation:
cause i got it right
a 10-mm-long glider with a mass of 680 kgkg (including the passengers) is gliding horizontally through the air at 38 m/sm/s when a 60 kgkg skydiver drops out by releasing his grip on the glider.
What is the glider's speed just after the skydiver lets go?
The glider's speed just after the skydiver lets go is approximately 39.52 m/s.
To answer this question, we can use the conservation of momentum principle. Before the skydiver lets go, the combined momentum of the glider and skydiver is:
Initial momentum = (mass of glider + mass of skydiver) * initial velocity
Initial momentum = (680 kg + 60 kg) * 38 m/s
When the skydiver releases his grip, the glider's mass is reduced by the skydiver's mass. Let v be the glider's velocity just after the skydiver lets go:
Final momentum = mass of glider * v
Since momentum is conserved:
(mass of glider + mass of skydiver) * initial velocity = mass of glider * v
Now, we can solve for v:
v = [(680 kg + 60 kg) * 38 m/s] / 680 kg
v ≈ 39.52 m/s
Just after the skydiver lets go, the glider's speed is approximately 39.52 m/s.
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can someone help plz
\(\\ \sf\longmapsto (side)^3\)
\(\\ \sf\longmapsto (5)^3\)
\(\\ \sf\longmapsto 125cm^3\)
Mass=750gNow
\(\\ \sf\longmapsto Density=\dfrac{Mass}{Volume}\)
\(\\ \sf\longmapsto Density=\dfrac{750}{125}\)
\(\\ \sf\longmapsto Density=7g/cm^3\)
Student one used bowling ball A in a bowling game against Student 2, who used bowling ball B. Use Newton’s Three Laws of Motion to explain the following:
Make a claim as to how Newton’s Three Laws of Motion can impact the bowling game for the 2 students. .
Use the image below and your background knowledge of how mass, acceleration, and force differ for the two bowling balls to support your claim, and provide reasoning as to how this evidence supports your claim.
Explain what variable the players could manipulate to maximize the force exerted on the pins.
Answer:
Newton’s Three Laws of Motion has a great impact.
Explanation:
Newton’s Three Laws of Motion has a great impact on the bowling game for the 2 students. When the student one throw ball to the student 2, the ball decrease its speed due to the gravity and opposing air. If these forces are removed from the system the ball will continue its motion till another force is applied on it. When the force applied to the ball it produces acceleration in the direction to the applied force. If the ball touches the ground it bounce back with equal force which is a reaction of the ground.