According to Newton's third law of motion the force exerted by the car on the wall and the force by the wall on the car are equal and opposite. But there will be no displacement for the wall.
What is collision?Collison is a short time force acting between two objects. There are both elastic and inelastic collision. In elastic collision, the kinetic energy and momentum of the colliding system is conserved whereas in inelastic collision, the kinetic energy is not conserved.
For any type of collision, we can apply Newton's third law of motion. This law states that, for every action there is an equal and opposite reaction. Therefore, in a collision, the force exerted by each object will be equal and opposite in direction.
Therefore, the force exerted by the car on the wall and the force by the wall on the car are equal and opposite. But there will be no displacement for the wall.
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8. An object was lifted to a height of 1234 cm. The object gained a gravitational potential energy of 4321 J. What was the mass of the object in grams?
9. An apple has a mass of 150g, when the apple is at a height of 1.9 m on an unknown planet, the apply has a GPE of 190 J, what is the value of gravity on the unknown planet?
10. A banana has a mass of 183g, when the apple is at a height of 2.8 m on an unknown planet, theapply has a GPE of 250 J. what is the value of gravity on the unknown planet?
A body of mass 3kg is dropped from a tower of height 250m. then its kinetic energy after 3 seconds will be
Answer:The kinetic energy of an object is equal to its mass times the square of its velocity, divided by 2.
Explanation:
Since the body is dropped from a height, it initially has no velocity. As it falls, it will accelerate due to the force of gravity. The acceleration due to gravity is approximately 9.8 m/s^2.
After 3 seconds, the velocity of the body will be 3*9.8 = 29.4 m/s. The kinetic energy of the body will be:
KE = (3 kg) * (29.4 m/s)^2 / 2 = 849.56 J
This is the kinetic energy of the body after 3 seconds of falling.
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If an object takes 5 seconds to fall off a building, how high is the building?
calculate the average speed of the cyclist travelling 100 meters in 40 seconds
To find the average speed of the cyclist, we need to divide the distance traveled by the time it took to travel that distance. So we would divide 100 meters by 40 seconds, which gives us 2.5 meters per second. This is the average speed of the cyclist.
Answer:
The Average Speed is 2.5metres per second
Explanation:
Using Distance,Time,Speed Triangle,
[tex]S = \frac{D}{T}[/tex]
[tex]S = \frac{100}{40}\\[/tex]
[tex]S = 2.5[/tex]
Hence , the average speed is 2.5m/s
Please help I have to turn it in tomorrow
Answer:
i think the answer is a
Explanation:
hope i am right
If 10.0 g of water is initially heated from 20°C to 100°C, and then it is continually heated through its phase change (it is vaporised), what is the total amount of energy necessary to carry out this process?
Answer:
The total amount of energy necessary to carry out this process is 22600 joules (J).
Explanation:
This is because the heat of vaporization (the energy required to change the state of water from liquid to gas) of water is 2260 J/g. Since 10.0 g of water is being heated, the total amount of energy needed is 10.0 g * 2260 J/g = 22600 J.
cinder block is sitting on a platform 20 m high. It weighs 79 N. The block has
energy. Calculate it.
Answer: 1580 J
Explanation:
Energy is in the form of gravitational potential energy. (GPE)
GPE = mgh , where m is the mass of the block, h is the height and g is the gravitational constant of 9.81 ms-2.
Hence,
Total energy = mass x gravitational constant x height
= Weight x height (since W = mg)
= 79 x 20 J
= 1580 J
Because Earth has a lot of nitrogen in its atmosphere and nitrogen has three atoms, this causes even more bluish coloring since three different paths are possible for any one photon (particle of light). Three paths means that more photons are scattered forward and backward than side-to-side, which will make the sky look bluer still.
A buildup of nitrogen in the atmosphere can result in pollutants like ozone and ammonia, which can reduce visibility, interfere with plant growth, and harm our capacity to breathe.
Does increase in nitrogen cause global warming?"Human nitrogen additions to the soil, in the form of fertilisers, strengthen the greenhouse effect: approximately 60% of nitrous oxide is emitted from fertilised fields, manures, and other agricultural sources," claims Mahesh Pradhan, a nutrient pollution specialist with the UN Environment Programme (UNEP).
AUSTRIA (Thomson Reuters Foundation) - Scientists said on Wednesday that rising nitrogen-based fertiliser use is raising emissions of a greenhouse gas 300 times more potent than carbon dioxide, endangering attempts to keep global warming within globally set limits.
With over 75% of all greenhouse gas emissions and almost 90% of all carbon dioxide emissions coming from fossil fuels like coal, oil, and gas, they are by far the biggest cause of climate change in the world.
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A car moves in a straight line at 20.0 m/s for 8.00 miles, then at 30.0 m/s for another 8.00 miles. a. Is the car's average speed less than, greater than, or equal to 25.0 m/s
The average speed of the car is 24 m/s. The average speed of the car is therefore below 25.0 m/s.
What is speed ?The description of rapidity. a change in the location of an object in either direction or speed. How fast something is going is determined by the distance travelled and the time required to cover that distance. Speed is a scalar quantity since it just has an arrow-like direction and no magnitude.
What is distance ?The entire movement of an item, independent of direction, is called distance. Distance may be characterized as the quantity of ground covered, regardless of the starting or finishing points of an item.
distance (d) = 9 miles = 14.4841 km
d = 14484.1 m
1 miles = 1609.34 m
t₁= 14484.1/ 20
= 724.2 sec
t₂= 14484.1/ 30= 482.8 sec
total time ( t) = t+t
t= 724.2+ 482.8 = 1207 sec
Vavg = 2d/t= 2*14484.1/1207
Vavg = 24m/s
24< 25
lessthan 25m/s
car average speed (Vavg) = 24 m/s.
Therefore, the car average speed is 24 m/s.
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A mass of 1.5 kg moves in a circle of radius 25 cm at 2.0 Hz. Calculate:
a) the velocity. b) the acceleration. c) the centripetal force acting on the mass.
Answer:
To solve this problem, you can use the following formulas:
Velocity (v) = 2πr * f
Acceleration (a) = v^2 / r
Centripetal force (F) = ma
In these formulas, r is the radius of the circle, f is the frequency of the circular motion, and m is the mass of the object.
a) To find the velocity of the mass, you can substitute the values given into the formula for velocity:
v = 2πr * f
= 2π(0.25 m) * 2.0 Hz
= 1.57 m/s
So, the velocity of the mass is approximately 1.57 m/s.
b) To find the acceleration of the mass, you can substitute the values given into the formula for acceleration:
a = v^2 / r
= (1.57 m/s)^2 / 0.25 m
= 4.45 m/s^2
So, the acceleration of the mass is approximately 4.45 m/s^2.
c) To find the centripetal force acting on the mass, you can substitute the values given into the formula for centripetal force:
F = ma
= 1.5 kg * 4.45 m/s^2
= 6.68 N
So, the centripetal force acting on the mass is approximately 6.68 newtons.
Lab motion
Table E: Average Speeds for Higher Racetrack
Time (Initial) |Time (Final) |Elapsed |Time |Average speed
| | | |
(s) (s) (s) (m/s)
1st ¼ of the Track
-------------------------------------------------------------------------------------------------------
2nd ¼ of the Track
-------------------------------------------------------------------------------------------------------
3rd ¼ of the Track
-------------------------------------------------------------------------------------------------------
Final ¼ of the Track
-------------------------------------------------------------------------------------------------------
R is the radius of speed curvature of the turn, g is the acceleration due to gravity, and μs is the coefficient of static friction.
θ is the angle of banking. For no slippage to occur even when the contribution of the frictional force in the centripetal force is not considered, we ignore the effect of friction and get the Time. Well, if the radius must be a single measurement, then the turn will be perpendicular.
While you're gathering necessary data, there's a discrepancy in your Average speed. Unless there are also tighter or unbanked turns, it's difficult to imagine the average speed=cornering speed.
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A worker is testing a multiple pulley system to estimate the heaviest object that he could lift. The largest downward force he can exert is equal to his weight, 875 N. When the worker moves the rope 1. 5 m, the object moves 0. 25 m. What is the heaviest object that he could lift?
Force is positive if the mass accelerates downward. Use the formula T = M x A to determine the tension in the rope.
How is the force in a pulley system calculated?That direction is the pull that is referred to as tension. As a result, the tension will point toward the string or rope and away from the mass.
A mass suspended by a string is pulled upward by the string, exerting an upper force that shifts the tension to the upper side.
For instance, you should know that T = 9g x 2m/s2 = 18gm/s2 or 18N when trying to calculate T in a straightforward pulley system with a linked mass of 9g and an upward acceleration of 2m/s2 (newtons). The direction in which a string expands changes when it passes over an ideal massless pulley, but the string's tension is unaffected.
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The impulse that the pelton wheel applies to the water is ___ the change in momentum of the water after hitting the flat paddle wheel?
The impulse that the pelton wheel applies to the water is equal to the change in momentum of the water after hitting the flat paddle wheel.
What is the pelton wheel about?Impulse is a measure of the force applied to an object over a period of time, and it is equal to the change in momentum of the object.
In the case of the pelton wheel, the force is applied to the water by the flat paddle wheel, and the change in momentum of the water is the result of that force.
Therefore, The impulse of the pelton wheel is therefore equal to the change in momentum of the water after it hits the paddle wheel.
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a telescope searching for newly formed stars would make the most discoveries if it were pointed
Yes, the center of the Milky Way is the most densely populated area of stars, and is therefore the most likely region to find newly formed stars.
What is the populated?
Populated refers to an area that has a large number of people residing in it. It is usually used to describe cities, towns, or other densely populated areas. Populated areas usually contain a variety of services and infrastructure to support their populations, such as schools, hospitals, transport links, and other amenities. Populated areas usually have higher rates of crime, pollution, and other problems associated with increased human activity.Populated refers to an area that has a high density of people living in it. It is usually used to describe cities and towns, but can also describe smaller areas, like neighborhoods.
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A 30,000-kg freight car is coasting at 0.850 m/s with negligible friction under a hopper that dumps 110,000 kg of scrap metal into it. (a) What is the final velocity of the loaded freight car
The freight car which is being dumped into the metal scrap has the final velocity of 0.18 m/s.
In this problem, we use the principle of conservation of linear momentum.
Given that,
Mass of the freight car m₁ = 30,000 kg
Mass of the hopper m₂ = 110,000 kg
Velocity of the freight car u₁ = 0.85 m/s
Velocity of the hopper u₂ = 0
Let the velocity of the loaded freight car = v
We need to find out v.
m₁ u₁ + m₂ u₂ = ( m₁ + m₂) v
After putting the values into the equation above, we have,
30,000 × 0.85 + 110,000 × 0 = (30,000 + 110,000) v
140,000 v = 25500
v = 0.18 m/s
Thus, the required velocity of the loaded freight car is calculated to be 0.18 m/s.
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Using the principle of conservation of energy and the final height the golf ball reaches after bouncing, determine the theoretical speed with which the ball must have left the floor (i.e on its way back up).
Mass: 0.0453kg
Initial height: 1m
Initial potential energy: 0.444J
Final height: 0.61m
Final potential energy: 0.271J
Efficiency: 61.0%
Answer:
2.58 m/s
Explanation:
To determine the theoretical speed at which the golf ball must have left the floor, you can use the principle of conservation of energy, which states that the total energy in a closed system remains constant. In this case, we can use the fact that the ball's potential energy changes as it rises and falls.
First, we know that the efficiency of the ball is 61.0%, so we can assume that 39% of the energy is lost as heat, sound, etc. We can calculate the initial kinetic energy (Ei) of the ball as:
Ei = Efficiency * (Initial Potential energy - Final Potential energy)
Ei = 0.61 * (0.444 - 0.271) = 0.119J
Now, we can use this value to calculate the velocity (Vi) of the ball as it left the floor, by using the equation of kinetic energy:
Ei = 0.5 * m * Vi^2
Where:
m = mass of the ball = 0.0453 kg
Vi = velocity of the ball when it left the floor
By substituting the values in the equation we get:
0.119 = 0.5 * 0.0453 * Vi^2
Solving for Vi:
Vi = sqrt(0.119 / (0.5 * 0.0453))
Vi ≈ 2.58 m/s
So, the theoretical speed with which the ball must have left the floor is approximately 2.58 m/s
Keep in mind that this is a theoretical speed and there may be a variance with real-world observations.
A single conservative force acting on a particle within a system varies as F=(−Ax+bx2)i^, where A and B are constants, F is in newtons, and x is in meters. (a) Calculate the potential energy function U(x) associated with this force for the system, taking U=0 at x=0. Find (b) the change in potential energy and (c) the change in kinetic energy of the system as the particle moves from x=2.00m to x=3.00m.
(a) The potential energy of the system to the conservative force acting on the particle, with Ui=0:
(b) From (a), U(2.00m)=2A–2.67B, and U(3.00m)=4.5A–9B.
ΔU=(4.5A−9B)−(2A−2.67B)=2.5A−6.33B
(c) For the entire system of which this particle is a member, this work is internal work and equal to the negative of the change in potential energy of the system: ΔK=−ΔU=−2.5A+6.33B.
Define kinetic energy?The ability of kinetic energy to perform work is arguably its most significant quality. Work is defined as a force operating on an object while it is moving. Energy and work are equivalent because of their tight relationship.It is described as the effort required to move a mass-based body from rest to the indicated velocity. The body holds onto the kinetic energy it acquired during its acceleration, unless its speed changes.Thermal energy is also known as heat energy. The power behind motion is known as kinetic energy. Thermal energy is a type of kinetic energy because it is generated by moving particles.To learn more about kinetic energy refer to:
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A proton moves at 3.80 105 m/s in the horizontal direction. It enters a uniform vertical electric field with a magnitude of 9.20 103 N/C. Ignore any gravitational effects. (a) Find the time interval required for the proton to travel 4.50 cm horizontally. 118.42 Correct: Your answer is correct. ns (b) Find its vertical displacement during the time interval in which it travels 4.50 cm horizontally. (Indicate direction with the sign of your answer.) mm (c) Find the horizontal and vertical components of its velocity after it has traveled 4.50 cm horizontally.
Answer:
(a) The time interval required for the proton to travel 4.50 cm horizontally is
t = (4.50 cm) / (3.80 x 105 m/s) = 118.42 ns
(b) The vertical displacement of the proton during the time interval is
dY = (F × t2) / 2m = (9.20 x 103 N/C × (118.42 ns)2) / (2 × 1.67 x 10-27 kg) = 0.0033 mm
(c) The horizontal and vertical components of the velocity after the proton has traveled 4.50 cm horizontally are
Vx = 3.80 x 105 m/s
Vy = (F × t) / m = (9.20 x 103 N/C × 118.42 ns) / (1.67 x 10-27 kg) = 1.90 x 105 m/s
A RL circuit is driven by an AC generator as shown in the figure. sin(ot) The voltages across the resistor and generator are ??.
O always out of phase O always in phase sometimes in phase and O sometimes out of phase Submit
Sometimes in phase and sometimes out of phase.The voltage across the resistor and generator will depend on the phase difference between the current and voltage in the circuit.
The voltage across the resistor and generator will depend on the phase difference between the current and voltage in the circuit. If the phase difference is 0°, then the voltage across the resistor and generator will be in phase. If the phase difference is 180°, then the voltage across the resistor and generator will be out of phase. In any other scenario, the voltage across the resistor and generator will be somewhere in between in phase and out of phase.
Sometimes in phase and sometimes out of phase.
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A box of weight 150 N is placed on
an inclined plane. The component
of the box's weight acting along
the plane is given by W'. What
would be the value of W", in
Newtons?
The value W' along inclined plane = (150 sin α ) N
W = m x g = 150 N --> based on case
W = weigth
m = massa
g = gravity acceleration
Fn = Normal force
Fn = m x g x cos α = W cos α = 150 N x cos α
W’ = m x g x sin α = W sin α = 150 N x sin α
Since the angle α is not known it will be still variable, so we could say that the W’ = (150 sin α ) N
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Shawn and his bike have a total mass of 44.0 kg. Shawn rides his bike 1.70 km in 11.0 min at a constant velocity. What is Shawn's kinetic energy?
The velocity of the bike is 2.57 m/s. Then the kinetic energy of the 44 kg mass is 145.3 J.
What is kinetic energy?Kinetic energy of an object is generated by virtue of its motion. Kinetic energy is related to the mass and velocity of the object by the expression written below:
Ke = 1/2 m v²
Given the distance travelled = 1.70 km = 1700 m
time taken = 11 min = 660 s
then velocity = distance/ time = 1700 /660 = 2.57 m/s
Total mass = 44 kg
Ke = 1/2 44 Kg × (2.57)² = 145.3 J
Therefore, the kinetic energy of Shawn and his bike is 145.3 J
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Write down whether quantity of potential kinetic and total energy
Potential energy is the power that a thing possesses as a result of where it is in relation to other objects.
What is Potential energy?The earth can pull you down through the force of gravity while doing work in the process, being at the top of a stairwell gives you more potential energy than standing at the bottom.
Two magnets have more potential energy when they are held apart than when they are near to one another. They will migrate near each other and begin working if you let them go.
The force acting on the two objects affects the potential energy formula. P.E. = mgh, where m is the mass in kilograms and g is the acceleration due to gravity, is the formula for gravitational force.
Therefore, Potential energy is the power that a thing possesses as a result of where it is in relation to other objects.
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a typical gps satellites orbit at an altitude of 2.0 x10^7 m. find (a) the orbital period, and (b) the orbital speed of such a satellite
the orbital period is 7200sec or 2hours and orbital speed is 7,27m/s
(a) The orbital period of a satellite is the time it takes for the satellite to make one full orbit around the Earth. To calculate the orbital period, we can use the equation: T = 2 * pi * (a^3/GM)^(1/2) where T is the orbital period, a is the semi-major axis of the orbit (which is equal to the altitude of the satellite), pi is approximately 3.14, G is the gravitational constant (approximately 6.67 x 10^-11 m^3/kgs^2), and M is the mass of the Earth (approximately 5.98 x 10^24 kg).Plugging in the given altitude of 2.0 x 10^7 m for a and the known values for pi, G, and M, we get:
T = 2 * pi * (2.0 x 10^7 m)^3/ (6.67 x 10^-11 m^3/kgs^2 * 5.98 x 10^24 kg)^(1/2)
Simplifying, we get:
T = 2 * pi * (8.0 x 10^21 m^3/ (4.03 x 10^34 kg*m^3/s^2))^(1/2)
T = 2 * pi * (1.98 x 10^13 s^2/kg)^(1/2)
T = 7200 sec (or 2 hours)
(b) The orbital speed is the distance traveled by the satellite in one hour. We can calculate the orbital speed using the equation v = 2πa/T
Plugging in the values of a and T we get :
v = 2π (2.0 x 10^7 m) / 7200 sec
v = 7,27 m/s
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How do you find torque with force and distance?
Torque = force x distance from point of rotation
Torque is a measure of the turning effect of an applied force about a specific point or axis. It is calculated by multiplying the force applied to an object by the distance from the point of rotation to the point where the force is applied. The greater the force or the longer the distance from the point of rotation, the greater the torque. The unit of torque is typically Newton-meters (N·m) in the International System of Units (SI) or pound-feet (lb·ft) in the imperial system. Torque is essential in various fields such as physics, mechanics, engineering and robotics.
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Define the following
a. Friction:
b.Sliding friction:
c.Static friction
d.Rolling friction
e.Air resistance
f. Terminal velocity
g.Gravity
h.Weight
i. Centripetal force:
j.Momentum
These are just personal definitions of the following. They aren't official ones that may come from your textbook, but they are still accurate.
a. Friction is a force that acts against forces in contact with an object.
b. Sliding Friction is a force that acts against the forces making an object slide (e.g. the y component of the object's weight force if it's on an incline)
c. Static Friction is a force that acts on an object that is still/not moving.
d. Rolling Friction is the force making an object roll.
e. Air resistance is a frictional force that acts to slow down a falling object.
f. Terminal velocity is the maximum an object can reach while in free fall due to air resistance.
g. Gravity is a mutual attractive force in between two objects.
h. Weight is the mass of an object multiplied by the gravitational force (usually 9.81 for objects on earth). Weight is a force acting against the normal force keeping objects from phasing through each other.
i. Centripetal force is a force that acts on an object that is turning. This force pulls the object to the outside of the turning track.
j. Momentum is defined by mv (mass times velocity). Momentum is not a force, it is the idea that the motion of an object can depend on its mass and velocity.
I would check official dictionaries, just to make sure these definitions align with your textbook's.
Consider the following reaction
2Mg(s) + 02 (9) 2Mgo (s)
If 21. 2 kcals of energy is released by this reaction, how many kJ
of energy does the reaction release? (1 cal = 4. 184 J) (Round off
decimal to nearest tenths)
In the given reaction, 2Mg(s) + O₂ (g) → 2MgO (s), 88.7 kJ of energy will be released.
The reaction 2Mg(s) + O₂ (g) → 2MgO (s) involves the release of energy from the system and hence it is an exothermic reaction. 21.2 kcals of energy is released from this reaction.
21.2 kcals = 21.2 × 10³ calories
1 cal = 4.184 J
For 21.2 × 10³ calories,
21.2 × 10³ cal × 4.184 = 88.70 × 10³ cal
To convert J to kJ, we divide it by 10³
88.70 × 10³ / 10³ = 88.70
Rounding off to nearest tenths, the amount of energy released by the given reaction in kJ = 88.7 kJ
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60 points!
What is the average time for the toy car to move 1.0 m on dirt?
21.2 s
22.4 s
23.1 s
63.7 s
Answer:
it should be 23.1
Explanation:
You have to look at the scale and then you calculate it
different between simple cell and dry cell
Answer:
Simple cell has liquid chemicals and it is difficult to carry from one place to another. Dry cell has no solution. So, it is easier to carry it from one place to another and there is no risk of spilling acid from the dry cell. So, dry cell is more useful than simple cell in our daily life.
What are the similarities and differences between static stretching and dynamic stretching?
The similarities and differences between static stretching and dynamic stretching are the dynamic stretch is a style of stretching that is more strenuous and physically stimulating, while the static stretch is a form of stretching that is slower and more relaxing.
Another difference between static and dynamic stretching is that after a dynamic stretch, you may feel stronger and have more muscle endurance and speed, whereas static stretching before an exercise diminishes these same qualities; To get the most out of your workout, perform dynamic stretching before you begin, and static stretching afterward. Static and dynamic stretching have similar benefits in lowering the risk of injury by increasing flexibility, balance, and body awareness.
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A heavy truck and a small truck roll down a hill. Neglecting friction, at the bottom of the hill the heavy truck has greater
acceleration.
speed.
momentum.
all of the above
none of the above
Correct option is A, A heavy truck and a small truck roll down a hill. Neglecting friction, at the bottom of the hill the heavy truck has greater acceleration.
Momentum and mass are directly proportional in direction. This is so because mass times velocity make up the equation for momentum. Another way to express this is as p = m*v, where p stands for momentum, m for mass, and v for velocity. As a result, momentum doubles if mass is increased by a factor of two but velocity remains constant.
p = m v . The equation demonstrates that momentum is directly related to an object's mass (m) and velocity (v). As a result, an object's momentum increases with increasing mass or velocity. The momentum of a large, swift object is larger than that of a small, slower object.
The definition of momentum is "mass in motion." Since every item has mass, if it is moving, it must have momentum because its mass is in motion. The amount of motion and the speed of the motion are the two factors that determine how much momentum an item possesses.
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