Answer:
The student took 400 seconds to run for 2 km
Explanation:
Average Speed
If an object travels a distance d in a time t regardless of the direction, the average speed is the quotient of the total distance traveled by the total time taken:
[tex]\displaystyle \bar v=\frac{d}{t}[/tex]
The student ran at an average speed of v=5 m/s and covered a distance of 2 km. Converting km to meters: d=2 km *1000= 2000 m. We must find the time the student needed run that distance, so we solve for t:
[tex]\displaystyle t=\frac{d}{\bar v}[/tex]
[tex]\displaystyle t=\frac{2000}{5}=400\ s[/tex]
The student took 400 seconds to run for 2 km
9)A 64 kg parent and a 16 kg child meet at the center of an ice rink. They place their hands together and push. (A) Is the
force experienced by the child more than, less than, or the same as the force experienced by the parent? (B) is the
acceleration of the child more than, less than, or the same as the acceleration of the parent? Explain. (C) If the
acceleration of the child is 2.5 m/s^2 in magnitude, what is the magnitude of the parent's acceleration?
Answer:
(A) The same
(B) More
(C) The magnitude of the parent's acceleration is 0.625 m/s²
Explanation:
The given parameters are;
The mass of the parent, m₁ = 64 kg
The mass of the child, m₂ = 16 kg
(A) By Newton's third law of motion, action and reaction are equal and opposite
Therefore, the action of the parent on the child is equal to the reaction of the child on the parent and vice versa
Therefore, the force experienced by the child is the same as the force experienced by the parent
(B) Newton's second law states that an objects acceleration is directly proportional to the applied force and inversely proportional to the mass of the object
Therefore, the parent and the child both experience the same force but the mass of the child is less than the mass of the parent and therefore, by Newton's second law, the acceleration of the child will be more than the acceleration of the parent for the same given force
(C) The acceleration of the child, a₂ = 2.5 m/s²
Let F₁ represent the force experienced by the parent, let F₂ represent the force experienced by the child and let a₁ represent the magnitude of the parent's acceleration
By Newton's third law, we have;
F₁ = F₂
Force, F = Mass, m × Acceleration, a
We can write, F = m × a
Therefore;
F₁ = m₁ × a₁ and F₂ = m₂ × a₂
∴ F₁ = F₂ gives;
m₁ × a₁ = m₂ × a₂
a₁ = (m₂ × a₂)/m₁ = (16 × 2.5)/64 = 0.625
∴ The magnitude of the parent's acceleration = a₁ = 0.625 m/s²
2. A 50.0 kg shell was fired from a cannon at earth's surface to a
maximum height of 400. m.
a. What is the potential energy at maximum height?
b. It then fell to a height of 100. m. What was the loss of PE as
it fell?
Answer: a) 196000 Joules
b) 147000 Joules
Explanation:
a. Potential energy is the energy possessed by an object by virtue of its position.
[tex]P.E=m\times g\times h[/tex]
m= mass of object = 50.0 kg
g = acceleration due to gravity = [tex]9.8ms^{-2} [/tex]
h = height of an object = 400 m
Putting in the values we get:
[tex] P.E=50kg\times 9.8ms^{-2}\times 400m=196000kgm^2s^{-2}=196000Joules[/tex] [tex](1kgm^2s^{-2}=1Joule )[/tex]
Thus the potential energy at maximum height is 196000Joules.
b. [tex] P.E=50kg\times 9.8ms^{-2}\times 100m=49000kgm^2s^{-2}=49000Joules[/tex] [tex](1kgm^2s^{-2}=1Joule )[/tex]
Thus loss in P.E = (196000Joules-49000Joules) = 147000 Joules
Why is more energy required to vaporise 1kg of water than to melt 1kg of ice?
(Please help, this is urgent)
Answer: The temperature change occurs from heat transfer if the ice melts and becomes liquid water. Similarly, energy is needed to vaporize a liquid, because the molecules in a liquid interact with each other via attractive forces.
Explanation:
Complete the following math operations giving the answer with the correct significant digits.
510x30
Group of answer choices
15
150,000
15,000
150
Answer:
15,000
Explanation:
According to O*NET, what are common skills needed by Emergency Medical Technicians? Check all that apply.
critical thinking
installation
technology design
active listening
service orientation
equipment maintenance
Career Explorations wasn't an options for subjects so I chose Physics. And the answer is 1, 4, and 5: critical thinking, active listening, and service orientation. It said on a website that equipment maintenance was an answer too but on the question on edg 2020 it said it wasn't
Answer:
Its just 1 4 an 5
Explanation:
i got it right
what happens if you shoot a bullet in the air and lands on your head
Answer:
most of the time the bullet will not hurt you but sometimes can hurt or kill you.
Using the acceleration value you calculated in part A what is the final velocity of the box when immediately before it hits the bottom of the ramp.
3pts. Create and fill in a data table for all five of the known and unknown kinematics values.
2pts. Select and apply the correct kinematics equation based on the kinematics data you are trying to solve for and the data you know.
1pt. Solve
Answer:
final velocity= gt= 9.8t
where t is time taken by the box to strike ramp
A gust of wind blowing east pushes against a ball. When will the wind do work on the ball? when the ball moves to the east when the ball moves to the north when the ball stays in one place when the ball moves north or south
Answer: when the ball moves to the east
Explanation:
Work is done when an external force makes an object move in the direction that it was forcing it to by transferring energy to it.
The wind is blowing to the east which means that it is exerting a force that is trying to move the ball to the east. For work to actually occur, the ball needs to move in the direction of the force being applied which is the east.
Answer:
simplified version of the person above me its option A
Explanation:
In which application is a magnet used to store information?
A. The needle on a compass
B. A recycling-center separator
C. The clasp on a necklace
D. The disk in a computer hard drive
Answer:
d the disk in a computer hard drive
Explanation:
because hard drive use magnetic memory tostore giga- and terabytes of data in computer.
The disk in a computer hard drive is an application that uses magnets to store information.
What are magnets?Magnets are materials which are produce magnetic properties and make use of magnetic fields.
Magnets are used on various appliances such as speakers, microphones, computer hard disks, electromagnets, etc.
Hard disks make use of the magnetic properties of magnets to store information.
Therefore, the disk in a computer hard drive is an application that uses magnets to store information.
Learn more about magnets at: https://brainly.com/question/16236550
#SPJ2
You drive 20 meters forward and then 10 meters backwards in 30 seconds. What is your average speed?
Answer:
10
Explanation:
a.s = D÷T
= (20+10=30)30÷30
=10
1 m/s is my average speed.
What is average speed?Average speed is the total distance travelled by an object to the total time taken.
i.e.
Average speed = Total distance travelled /Total time taken
[tex]\overline{v}[/tex] = Δx/Δt
According to the question.
Total distance travelled by me = 20m +10m = 30m
Total time taken by me = 30 sec
By using the formula of average speed
[tex]\overline{v}[/tex] = Δx/Δt
= [tex]\frac{30m}{30s}[/tex]
=1 m/s
Hence,1 m/s is my average speed.
Learn more about average speed here:
https://brainly.com/question/9834403
#SPJ2
What are the forces like in a collision?
Answer:
The forces are a convergent
Explanation:
An 8.0-kg history textbook is placed on a 1.25-m high desk. How large is the
gravitational potential energy of the textbook-Earth system relative to the
floor?
i’ll give brainliest
Answer:
GPE=98J if the given gravity is 9.8 but the gravity is 10 it will be 100J
Explanation:
GPE=mgh so m=8kg g=9.8m/s^2 or 10J h=1.25m
so GPE=8kg×9.8 or 10 m/s^2×1.25m
GPE=98J if the given gravity is 9.8 and GPE=100 if the given gravity is 10.but ask your teacher (asker) and don't forget those formula
The gravitational potential energy of an object is directly proportional to the mass of the object. The gravitational potential energy of the object is 98 Joule.
What is gravitational potential energy?The energy acquired by an object due to its vertical position or height is defined as the gravitational potential energy. This energy mainly depends on the mass and height of the object.
The greater the mass of an object, higher is the gravitational potential energy and if greater is the height of the object, more will be the gravitational energy experienced by it.
The formula used to calculate the gravitational potential energy is:
GPE = mgh
m = Mass of the object
g = Acceleration due to gravity
h = Height of the object
GPE = 8.0 × 9.8 × 1.25 = 98 Joule
Thus the gravitational potential energy is 98 Joule.
To know more about gravitational potential energy, visit;
https://brainly.com/question/19768887
#SPJ7
El sargento Conejero toma el sol en su colchoneta, de 2 m2 de superficie, flotando en el agua de la piscina (d = 1 g/cm3 ). Si observamos que ésta se hunde 2,7 cm, ¿cuál es el peso del sargento? (Desprecia el peso de la colchoneta).
Answer:
W = 529.2 N
Explanation:
We can solve this problem using the translational equilibrium equation, where the forces are the weight of the sergeant and the thrust of the water given by Archimedes' principle
B - W = 0
where the thrust is
B = ρ g V_liquid
The volume of the displaced liquid is
V = A h
we substitute
ρ g A h = W
We reduce the magnitudes to the SI system
h = 2.7 cm = 0.027 m
ρ = 1 g / cm3 = 1000 kg / m³
let's calculate
W = 1000 9.8 2 0.027
W = 529.2 N
7. A 25 N block is lowered 1.2 m by a 20 N force.
a. Draw a free-body diagram of the forces acting on the block.
b. How much work does the force of gravity do on the box? Is this work positive or negative?
c. How much work does the applied force do on the box? Is this work positive or negative?
Answer:
this answer your question
The free-body diagram of the forces acting on the block is attached.
Work done by the force of gravity = 30 Joule (positive).
Work done by the applied force = 24 Joule (negative).
What is work done?A force must be applied in order for work to be completed, and there must also be motion or displacement in the force's direction.
The amount of force multiplied by the distance moved in the force's direction is known as the work done by a force acting on an item. Work has no direction and only magnitude. Work is a scalar quantity as a result.
Given parameters:
Weight of the block acting downwards; W = 25 N.
Force applied on the block in upward direction; F = 20 N.
Displacement of the block in downwards; s = 1.2 m.
So, work done by the force of gravity on the box W = F·s = Fscos0° = Fs = 25×1.2 Joule = = 30 Joule.
And, work done by the applied force the box W = F·s = Fscos180° = -Fs = -20×1.2 Joule = = - 24 Joule
Hence, the force of gravity do positive work of magnitude 30 joule on the box and the applied force do negative work of magnitude 24 Joule on the box.
Learn more about work here:
https://brainly.com/question/18094932
#SPJ2
3 resistors of 3,4 and 12 ohm are there. How would you connect so as to get a resistance more than 5 oh, but less than 7 ohm show using calculations and a diagram
Answer:
Connecting the 4-ohm and 12-ohm in parallel and followed by the 3-ohm resistor in series. A scheme of the configuration is attached below. Please see the file attached below to know the diagram.
Explanation:
There is the following solution that satisfies all requirements indicated on statement:
Connecting the 4-ohm and 12-ohm in parallel and followed by the 3-ohm resistor in series. A scheme of the configuration is attached below.
[tex]R = \frac{(12\,\Omega)\cdot (4\,\Omega)}{12\,\Omega+4\,\Omega}+3\,\Omega[/tex]
[tex]R = 6\,\Omega[/tex]
Which observes all design requirements.
A sailboat started its journey at 6:30am and reached the destination at 6:30pm. If the distance of the journey was 144 miles, what was the sailboats average speed?___mph
Answer:
The sailboats average speed was 13 mph.
Explanation:
To calculate the speed of the boat first calculate the total ammountof hours it took the boat to get to its destination. Then divide 144 by that number which comes out to 13.
The average speed of the sailboat is determined as 12 miles per hours.
What is average speed?
The average speed of an object in motion is obtained by dividing the total distance traveled by the object with the time spent in the entire journey.
v = total distance/total time
where;
total distance = 144 milestotal time = from 6:30am to 6:30pm = 12 hoursv = 144/12
v = 12 mph
Thus, the average speed of the sailboat is determined as 12 miles per hours.
Learn more about average speed here: https://brainly.com/question/6504879
#SPJ2
Which statement best describes balancing equations and the law of conservation of mass?
There are more atoms in the reactants than in the products, and the total mass is the same in the reactants and in the products.
The number of atoms is the same in the reactants and in the products, and the total mass is the same in the reactants and in the products.
There are fewer atoms in the reactants than in the products, and the total mass is less in the reactants than in the products.
There are more atoms in the reactants than in the products, and the total mass is higher in the reactants than in the products.
Answer:
it would be c, there are fewer atoms in the reactants than in the products, and the total mass is less in the reactants than in the products.
Explanation:
Answer:
ccccccccccccccccc
Explanation:
:DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
··
ω
Δ
ω
How much thermal energy is
needed to change 3.00 x 102 g of ice at -30.0°C
to water vapor at 130.0°C?
Answer:
Qt = 940500 [J]
Explanation:
In order to solve this problem and understand it well, we must analyze that the ice melts or changes phase at a temperature of 0 [°c], then the water at a temperature of 100 [°C] evaporates or changes phase. That is, we have 5 different stages of water (initially in the form of ice), which are:
-) From -30 [°C] to 0 [°C] = Sensible change of temperature
-) At 0 [°C] = Latent heat of melting ice = 334 x 10³ [J/kg]
-) From 0 [°C] to 100 [°C] = Sensible change of temperature
-) At 100 [°C] = Latent heat of fusion for water = 2260 x 10³ [J/kg]
-) From 100 [°C] to 130 [°C] = Sensible change of temperature (superheating)
We can calculate the sensible heat of any process with the following expression:
[tex]Q=m*C_{p}*(T_{f}-T_{i})[/tex]
where:
Q = heat or thermal energy [J]
m = mass of the body or substance = 300 [g]
Cpw = specific heat of the water = 4180 [J/kg*°C]
Cpi = specific heat of the ice = 2090 [J/kg*°C]
Tfinal = final temperature of the process [°C]
Tinicial = initial temperature of the process [°C]
And for some latent heat process, we can calculate the thermal energy using the following expression:
[tex]Q_{lat}=m*Dh_{fus/eva}[/tex]
where:
Dhfus/eva = Fusion heat or latent heat [J/kg]
So, we need to calculate the fice processes.
[tex]Q_{1}=0.3*2090*(0-(-30))\\Q_{1}=18810 [J]\\Q_{2}=0.3*334*10^{3} \\Q_{2}=100200[J]\\Q_{3}=0.3*4180*(100-0)\\Q_{3}=125400[J]\\Q_{4}=0.3*2260*10^{3}\\Q_{4}=678000[J]\\Q_{5}=0.3*2010*(130-100)\\Q_{5}=18090[J][/tex]
And the final step is the sum of all the five heat processes.
[tex]Q_{t}=Q_{1}+Q_{2}+Q_{3}+Q_{4}+Q_{5}\\Q_{t}=18810+100200+125400+678000+18090\\Q_{t}=940500[J][/tex]
How many meters are in 45 centimeters?
Explanation:
100 CM = 1 m
45 CM = 45 / 100 = 0.45 m
hope it helps:)
Answer:
0.45 meters ar three in 45 centimeters
Write a hypothesis about the use of an object’s physical characteristics to determine its density. Use the format "if . . . then . . . because . . .” and be sure to answer the lesson question "How can the density of an object be determined?” BE ORIGINAL AND SIMPLE
Answer:
If an object has a high density then the molicules making up that object are closly packed togeather. Because of this, objects with a higher density will have more mass than objects of the same size that have a lesser density.
Answer:
If an object has a high density then the molicules making up that object are closly packed togeather. Because of this, objects with a higher density will have more mass than objects of the same size that have a lesser density.
Explanation:
A ball is gently dropped from a height of 20 m. If its velocity increases uniformly at the rate of
10m s -2 , with what velocity will it strike the ground? After what time will it strike the Ground?
Answer:
The ball strikes the ground at 20 m/s after 2 seconds
Explanation:
Free Fall Motion
Any object that is being acted upon only by the force of gravity is said to be in a state of free fall.
If an object is dropped from rest in a free-falling motion, it falls with a constant acceleration called the acceleration of gravity, which value is assumed as [tex]g = 10 m/s^2[/tex].
The final velocity of a free-falling object after a time t is given by:
vf=g.t
The distance traveled by a dropped object is:
[tex]\displaystyle y=\frac{gt^2}{2}[/tex]
If we know the height h from which the object was dropped, we can find the time it takes fo hit the ground:
[tex]\displaystyle t=\sqrt{\frac{2h}{g}}[/tex]
The ball is dropped from a height of h=20 m. The time taken to strike the ground is:
[tex]\displaystyle t=\sqrt{\frac{2*20}{10}}[/tex]
t = 2 s
The velocity at which the ball strikes the ground is:
vf = 10 * 2
vf = 20 m/s
The ball strikes the ground at 20 m/s after 2 seconds
A railroad car undergoes an acceleration of 2.00 m/s2 when a net force of 40,000. N acts upon it. What is the mass of the railroad car?
Answer:
The mass of the railroad car is 20,000 kg
Explanation:
Mechanical Force
According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:
F = ma
Where:
a = acceleration of the object.
m = mass.
F = Net force
The railroad car undergoes an acceleration of [tex]a=2\ m/s^2[/tex] when a net force of F=40,000 N acts upon it.
It's required to find the mass of the railroad car, which can be done by solving the formula for m as follows:
[tex]\displaystyle m=\frac{F}{a}[/tex]
Substituting:
[tex]\displaystyle m=\frac{40,000}{2}=20,000[/tex]
The mass of the railroad car is 20,000 kg
What would the products of a double-replacement reaction between Na2S
and MgF2 be?
A. NaF and MgS
B. MgF and Nas
C. F2S and MgNa2
D. MgF2 and Nas
Answer:
A. NaF and MgS
Explanation:
The reaction equation is given as:
Na₂S + MgF₂ → 2NaF + MgS
The product of this reaction is NaF and MgS.
In a double displacement reaction there is an actual exchange of partners to form new compounds. This reaction takes place between ionic compounds.
The driving force for the reaction is:
formation of an insoluble precipitateformation of water or any other non-ionizing compound liberation of a gaseous product.What else is produced during the replacement reaction of magnesium and hydrochloric acid? Mg + 2HCl H2 + ________ MgCl2 Mg2Cl2 Mg2Cl MgCl
Answer:
A
Explanation:
MgCl2
Answer:
its MgCl2
Explanation:
i got it on edge
Gravitational force depends on __________ and __________.
a.
mass, distance
c.
distance, strength
b.
mass, strength
d.
strength, speed
Please select the best answer from the choices provided
A
B
C
D
Answer: pretty sure it’s A
Explanation:
please answer this question
Answer:
11.a) Car B is faster than Car A. This is because Car B covers more distance in less time, whereas Car A covers less distance in more time. Now, as we know that distance is directly proportional and time is inversely proportional to speed. In Car B, a larger distance and less time and a smaller distance and more time in Car A, indicates that the speed of Car B is more than the speed of Car A.
b) Car B accelerates faster than Car A. We know that, the acceleration is directly proportional to the change in linear velocity and inversely proportional to time taken. Here, The overall journey of Car B is short, whereas for Car A, it's longer. Also, as previously mentioned that the final speeds of Car B is more than Car A [remembering that both Cars start from the origin(rest)]. Hence, the change of velocity in Car B is more than Car A. Hence so.
Скільки тепла отримає цинкове тіло масою 2 кг, якщо воно підвищить свою температуру з 10 ° C до 60 ° C.
Answer:
39000 Дж теплової енергії поглинається тілом цинку.
Explanation:
З наведеного вище питання із запитання були отримані наступні дані:
Маса (М) = 2 кг
Початкова температура (T₁) = 10 ° C
Кінцева температура (T₂) = 60 ° C
Тепло (Q) =?
Далі ми перетворимо 2 кг у грами (g). Це можна отримати наступним чином:
1 кг = 1000 г.
Отже,
2 кг = 2 кг × 1000 г / 1 кг
2 кг = 2000 г.
Таким чином, 2 кг еквівалентно 2000 г.
Нарешті, ми визначимо тепло, що поглинається тілом цинку, як показано нижче:
Маса (М) = 2000 г.
Початкова температура (T₁) = 10 ° C
Кінцева температура (T₂) = 60 ° C
Питома теплоємність (С) цинку = 0,39 Дж / гºС
Тепло (Q) =?
Q = MC (T₂ - T₁)
Q = 2000 × 0,39 (60-10)
Q = 780 × 50
Q = 39000 Дж
Отже, 39000 Дж теплової енергії поглинається тілом цинку.
HELP PLS !!!!!!!!!!!!!!!!!!!!]
A 13.3 kg box sliding across the ground
decelerates at 2.42 m/s2. What is the
coefficient of kinetic friction?
(No unit)
Answer:
0.25
Explanation:
According to newtons law of motion
\sum F_x = ma
F_f = ma
nR = ma
nmg = ma
ng = a
n = a/g
g is the acceleration due to gravity
Given
a = 2.42m/s²
g = 9.8m/s²
Substitute into the formula;
n = 2.42/9.8
n = 0.25
Hence the coefficient of kinetic friction is 0.25
If you drop a watermelon and a penny off the roof of the school, which one
would hit the ground first?
Answer:
watermelon?
Explanation:
its heavier so the weight would make it drop faster
im not sure if this is a trick question so
Answer:
Watermelon because the weight of it is heavy and it would push itself on the ground
Identify two factors that increase the electric force between objects
Answer: The distance between particles, and the amount of electric charge they carry.
Explanation:
Charles Coulomb wanted to figure out the strength of the force between two objects and these were the two most independent factors.