Imagine that you throw a rock into the air. When you release the rock, it is moving at 19.4 m/s. The rock flies straight up into the air and returns back to your hand. For how long was the rock in the air? Note: acceleration due to gravity is -9.81 m/s/s.

Answers

Answer 1

Answer:

4 s

Explanation:

The following data were obtained from the question:

Initial velocity (u) = 19.4 m/s.

Acceleration due to gravity (g) = –9.81 m/s²

Total time (T) =.?

Next, we shall determine the time take by the rock to get to the maximum height. This can be obtained as follow:

NOTE: At maximum height, the final velocity is zero.

Initial velocity (u) = 19.4 m/s.

Acceleration due to gravity (g) = –9.81 m/s²

Final velocity (v) = 0 m/s

Time taken to reach the maximum height (t) =.?

v = u + gt

0 = 19.4 + (–9.81 × t)

0 = 19.4 – 9.81t

Collect like terms

0 – 19.4 = –9.81t

–19.4 = –9.81t

Divide both side by –9.81

t = –19.4 / –9.81

t ≈ 2 s

Thus, it took approximately 2 s for the rock to reach its maximum height.

Finally, we shall determine the total time spent by the rock in the air as follow:

Time taken to reach the maximum height (t) = 2 s

Total time spent in air (T) =?

The total time (T) spent by the rock in the air will be two times the time taken (t) to reach the maximum height i.e

T = 2t

t = 2 s

T = 2 × 2

T = 4 s

Therefore, the rock spent approximately 4 s in the air.


Related Questions

Sand is made of tiny pieces of rock that have been worn
down by wind and water. Explain why the formation of
sand is a physical change.

Answers

The formation of sand is physical damage because the rock that is worn down is basically broken. The rocks are broken.

Answer:

Sand is a form of physical change because it shows how one object is being worn out (broken down) into another object by nature.

Explanation:

Can someone please help me

Answers

Answer:

grams= 4.8e-5

kilograms= 4.8e-8

centigrams= 0.0048

dekagrams= 4.8e-6

Explanation:


A ball is thrown upward in the air with an initial velocity of 40 m/s. How long does it take to
reach back to the point it was thrown from?

Answers

Answer:

You need the definition of acceleration (a=Vf-Vi/t) and 1 equation of linear motion (deltaX = Vi×t + 1/2×a×t^2). Since you know a is constant (gravity) and you know your initial Vi to be 40 m/s and your final velocity Vf to be zero (maximum height), then you can use thhe definition of acceleration to find time.

-9.81m/s^2 = (0-40m/s)/t

t = (-40)/(-9.81) s

t = 4.077s

Now that you have time, you should know all but deltaX in the equation of linear motion.

dX = (40m/s)(4.077s) + (1/2)(-9.81m/s^2)(4.077s)^2

dX = (163.099m) — (81.549m)

dX = 81.55m

A rock climber is going up a narrow space between two vertical rocks. The distance between the rocks allows the climber to brace herself using friction, where her feet are flat and in contact with one rock to the left, and her legs are straight horizontal and her back is flat against a rock on the right. The coefficient of static friction between her shoes and the rock on the left is 1.2, and between the rock at right and her back is 0.8. The climber relaxes until she is on the verge of slipping on both sides.
(a) Draw a FBD for the climber
(b) What fraction of her weight is supported by the frictional force on her shoes?

Answers

Answer: b

Explanation:

WHat is the correct definnition for recovery heart rate ?

Answers

Answer:

when your heart rate is not high than normal or lower than normally

Explanation:

Recovery heart rate is when your heart recovers from a certain heart rate eg high heart rate or even low heart rate this means you heart is now functioning normally .

Answer:

Number of beats per minute the heart drops after exercise.

1)
You travel east at 50 km/hr and then north at 75 km/hr. What is your Resultant Velocity in km/h?
(Remember the angle) (5pts)

Answers

Answer:

15

Explanation:

The Plateau of Tibet is a dry place. Do you think the wide-leafed plant fossils found on the plateau could grow there today? Explain your answer.

Answers

No, I dont think that they could grow there now in this day and age becuase the Plateu of Tbiet is very dry and also a little bit dusty. They barely even have grass down there. Wide leaf plants susually grow somewhee like the rainforest where it is warm, sunny, and rainy but in a place like Tibet, I don't think that they would be able to survive there.

Answer:

No. The leaves are similar to those of plants found in lower elevations with plenty of rainfall, like the plants seen at the lower elevations of the Himalayas. Because the Plateau of Tibet has risen over time, it is not likely that these plants could live in these colder climates.

Explanation:

Sample answer from pluto

50 POINTS PLSS
Your car is initially at rest when your hit that gas and the car begins to accelerate at a rate of 2.857 m/s/s. The acceleration lasts for 15.5 s. What is the final speed of the car and how much ground does it cover during this acceleration?

Answers

Answer:I think the answer is 5.43 I don’t rlly know

Explanation:

show answer No Attempt 50% Part (b) Calculate the non-relativistic speed of these electrons v in m/s.

Answers

Complete Question

The complete question is shown on the first uploaded image

Answer:

The value is  [tex]v = 9.18 *10^{6} \ m/s[/tex]

Explanation:

From question we are told that

  The potential  difference is  [tex]\Delta V = 0.24 kV = 0.24 *10^{3} \ V[/tex]

Generally the the non-relativistic speed of these electrons  is mathematically represented as

       [tex]v = \sqrt{\frac{2 * e * \Delta V}{m} }[/tex]

Here  m is the mass of an electron with value [tex]m = 9.11 *10^{-31 } \ kg[/tex]

           e  is the charge on an electron with value  [tex]e = 1.60 *10^{-19} \ C[/tex]

So

        [tex]v = \sqrt{\frac{2 * 1.60 *10^{-19} * 0.24 *10^{3} }{9.11*10^{-31}} }[/tex]

=>   [tex]v = 9.18 *10^{6} \ m/s[/tex]

explain why a wrecking ball can destroy a building, but a yo-yo cant. Use the term kinetic energy in your explanation.

Answers

released weight increases in velocity.

momentum increases as force increases.

momentum= mass x velocity

the wrecking ball has a bigger mass and weight.

the mass of the weight of the wrecking ball is constant, the velocity of the weight as it swings must be increased if momentum is going to be increased.

The kinetic energy of a body determines it's level of impact on the object in which it comes in contact with. Hence, the much larger kinetic energy exhibited by a wrecking ball compared to a yo-yo means that is has a much larger impact on a building than a yo-yo.

Kinetic Energy = 0.5mv²

The kinetic energy of a body is a factor of it's velocity and mass as they are directly proportional.

The wrecking ball has a very large mass which is thousands of times larger than that of a yo-yo. Also, the velocity at which a wrecking ball is launched is higher than the velocity of a yo-yo.

This means that the kinetic energy of a wrecking ball is much higher than that of yo-yo. Hence, having much greater impact on a building compared to a yo-yo.

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Newton’s third law says that every time there is an interaction force, there is also a force that is ______________________ in size and acts in the ____________________________ direction .

Answers

newton’s third law states:
1. equal
2. opposite

Answer:

equal, opposite

Explanation:

Newton’s third law says that every time there is an interaction force, there is also a force that is equal in size and acts in the opposite direction .

can you pls give a question about science. like why does the sky blue? PLS HELPPP ASAP ​

Answers

I can why do plants grow fast?

The most interpersonal constructive passion response to relational conflict is..

Answers

Answer:

loyalty

Explanation:

Are these bones axial, appendicular
or both?

Answers

Answer:

Axial and Appendicular Skeletons The axial skeleton forms the central axis of the body and consists of the skull, vertebral column, and thoracic cage. The appendicular skeleton consists of the pectoral and pelvic girdles, the limb bones, and the bones of the hands and feet. Figure 6.41.

Explanation:

A car is pushed and travels 12 m. The same car is then pushed and it travels 15m. What
could have happened? Select 2 answers.
The mass was decreased
The force was increased
The force was decreased
The mass was increased

Answers

2 Answers: Choice A, Choice BMass was decreasedForce was increased

=========================================

Explanation:

If the force is kept the same, but the mass was decreased, then the car will travel further. The less mass an object has, the less inertia it has. Inertia is the tendency for the object to stay at rest if it's initially at rest (or the tendency for the object to stay in motion if already in motion).

If the mass is kept the same, but the force was increased, then the object will travel further than before. The same idea applies as discussed in the last paragraph.

------

If the force was decreased and mass kept the same, then there is less push, which results in the object traveling a shorter distance. If the mass is increased but the force kept the same, then the object moves a shorter distance because there's more inertia to overcome. There are more particles needed to be moved and they resist motion if at rest.

Which atmospheric layer gets warmer as altitude increases and contains the ozone layer?

Answers

Answer:

stratosphere

Explanation:

In the stratosphere, temperature increases with altitude. The stratosphere contains the ozone layer, which protects the planet from the Sun's harmful UV radiation.

Stratosphere is the atmospheric layer which gets warmer as the altitude increases and contains the ozone layer.

What is Stratosphere?

The stratosphere is a layer of the Earth's atmosphere. It is the second layer of the atmosphere as we go upward into the atmosphere height. The troposphere is the lowest layer of the globe, which is present right below the stratosphere. The next higher layer of the atmosphere above the stratosphere is the mesosphere.

In the stratosphere layer, the temperature increases with the increase in the altitude range. The stratosphere layer contains the ozone layer, which works in the protection of the planet from the Sun's harmful ultraviolet radiations which could lead to cancer.

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PLZ HELP!!!!!!! ILL GIVE U BRAINLIEST

Answers

Answer:

Claim: Heart Rate for Sarah and Matt (this would be the homeostasis AT REST and throughout the graph time)

Evidence: The Graph and the HR/S and its evidence towards the heart rate/beats every 15 seconds, due to the homeostasis being a specific time limit and due to the specific heart rate of Matt and Sarah ONLY.

Explanation: A/B Checkpoint throughout the homeostasis (this would be heart rate/trial throughout the time of the graph)

Conclusion: Matt was further away ONLY BECAUSE Sarah has a higher Heart Rate during the time on the graph, which can represent how long they did something to increase/decrease from and where the homeostasis would be located.

Answer:

Claim: Heart Rate for Sarah and Matt (this would be the homeostasis AT REST and throughout the graph time)

Evidence: The Graph and the HR/S and its evidence towards the heart rate/beats every 15 seconds, due to the homeostasis being a specific time limit and due to the specific heart rate of Matt and Sarah ONLY.

Explanation: A/B Checkpoint throughout the homeostasis (this would be heart rate/trial throughout the time of the graph)

Conclusion: Matt was further away ONLY BECAUSE Sarah has a higher Heart Rate during the time on the graph, which can represent how long they did something to increase/decrease from and where the homeostasis would be located.

Please help me with physics homework I just need help with C and D. Picture is included

Answers

Answer:

For C is B and for D is A

Explanation:

B because that's where the b car will do all the force to go up, and A because there the car doesn't have to do any force other than the natural, and it already brings that on it's own.

Which best describes a difference between laser light and regular light?
Laser light is less concentrated.
Laser light has a beam that spreads out.
O Laser light is made of one specific color.
O Laser light pumps out light particles one at a time.

Answers

Answer: the correct answer should be B

Explanation:

The statement that, best describes a difference between laser light and regular light is laser light is made of one specific color.

What is laser light?

A laser light is a light produced by a laser

Laser itself,  is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.

Difference between laser light and regular lightRegular light is non-directional and inconsistent, while laser light shows directional and highly consistent distribution.Regular light is a mixture of electromagnetic waves of different wavelengths while Laser light is monochrome (one colour).

Thus, the statement that, best describes a difference between laser light and regular light is laser light is made of one specific color.

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What is the rate of acceleration of a hammer whose head goes from moving -2 m/s (downward) to +0.5 m/s (upward) when it hits and bounces off a hard rock ? The actual bounce takes 0.025 seconds

Answers

Answer:

[tex]a=100\ m/s^2[/tex]

Explanation:

Given that,

Initial velocity, u = -2 m/s

Final velocity, v = =.5 m/s

Time, t = 0.025 s

We need to find the rate of acceleration of a hammer. Acceleration is equal to the change in velocity divided by the time taken.

[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{0.5-(-2)}{0.025}\\\\a=100\ m/s^2[/tex]

So, the acceleration of the jet is [tex]100\ m/s^2[/tex].

The path of a projectile fired at an angle above the horizontal is best described as

Answers

I agree it only makes sense

Which of the following is not a part of the appendicular skeleton
a. femur
b. scapula
c.phalanges
d.hyoid

Answers

Answer:

Hyoid

Explanation:

The hyoid is located in the neck area, not the limbs.

Your are part of a team to help design the atrium of a new building.Your boss, the manager of the project, wants to suspend a 6.2 kg sculpture high over the room by hanging it from the ceiling using thin, clear fishing line (string) so that it will be difficult to see how the sculpture is held up. The only place to fasten the fishing line is to a wooden beam which runs around the edge of the room at the ceiling.The fishing line that she wants to use will hold 10 kg so she suggests attaching two lines to the sculpture to be safe. Each line would come from the opposite side of the ceiling to attach to the hanging sculpture. Her initial design has the first line making an angle of 12.67∘with the ceiling and the second line making an angle of 16.15∘ with the ceiling. She knows you took physics, so she asks you if her design can work.
How much force would the first line exert on the beam holding it up?
Assume that g=9.8 m/s−2.

Answers

Answer:

The answer is below

Explanation:

Given that the mass of the sculpture (m) = 6.2 kg, [tex]\theta_1=12.67^o,\theta_2=16.15^o[/tex]

[tex]Sum\ of\ horizontal\ force\ is\ zero\ hence:\\\\T_1cos(\theta_1)=T_2cos(\theta_2)\\\\T_1=\frac{T_2cos(\theta_2)}{cos(\theta_1)}\\ \\Sum\ of\ vertical\ force\ is\ zero:\\\\T_1sin(\theta_1)+T_2sin(\theta_2)=mg\\\\\frac{T_2cos(\theta_2)}{cos(\theta_1)}sin(\theta_1)+T_2sin(\theta_2)=mg\\\\T_2=\frac{mg}{\frac{cos(\theta_2)}{cos(\theta_1)}sin(\theta_1)+sin\theta_2} \\\\T_2=\frac{6.2*9.81}{\frac{cos(16.15)}{cos(12.67)}sin(12.67)+sin16.15} =123.1\ N\\\\[/tex]

[tex]T_1=\frac{T_2cos(\theta_2)}{cos(\theta_1)}=121.2\ N[/tex]

7. A 2kg block is acted on by two forces F1 and F2 as shown in the diagram. If the magnitude of F1 = 13N and F2 = 11N. If the coefficient of kinetic friction is .23, find (A) The normal force exerted on it by the floor. (2 pts) (B) The acceleration on of the block (2 pts)

Answers

Answer:

A.) 17.04 N

B.) 10.76 m/s^2

Explanation:

Given that a 2kg block is acted on by two forces F1 and F2 as shown in the diagram. If the magnitude of F1 = 13N and F2 = 11N. If the coefficient of kinetic friction is .23,

A.) To find the normal force exerted on it by the floor, we need to first calculate the vertical forces of the ropes.

The vertical force on F1 = 13 sin 30

F1 = -6.5 N

The vertical force on F2 = 11 sin 21

F2 = 3.94

The resultant force = - 6.5 + 3.94

Resultant force = - 2.56

The normal force = mg - 2.56

The normal force = 2 × 9.8 - 2.56

The normal force = 19.6 - 2.56

The normal force = 17.04 N

(B) The acceleration on of the block will be achieved by first calculating the horizontal force.

For F1 = 13Cos 30

F1 = 11.26N

For F2 = 11 cos 21

F2 = 10.27

the resultant force = 11.26 + 10.27

Horizontal force = 21.53N

Force = mass × acceleration

21.53 = 2 × a

a = 21.53 / 2

Acceleration a = 10.76 m/s^2

A coin is rolling across a table at 0.23 m/s. It rolls off the table and lands 0.15 meters away from the edge of the table. How high is the table? Show all your work.​

Answers

Answer:

The table is 2.08 m high

Explanation:

Horizontal Motion

When an object is thrown horizontally with a speed vo from a height h, the range or maximum horizontal distance traveled by the object can be calculated as follows:

[tex]\displaystyle d=v\cdot\sqrt{\frac {2h}{g}}[/tex]

If we know the range d = 0.15 m and the speed v = 0.23 m/s, we can solve the above equation for h:

[tex]\displaystyle h=\frac{d^2\cdot g}{2v^2}[/tex]

[tex]\displaystyle h=\frac{0.15^2\cdot 9.8}{2\cdot 0.23^2}[/tex]

[tex]\boxed{h=2.08\ m}[/tex]

The table is 2.08 m high

When the force applied to an object increases, the motion of the object​

Answers

Answer:

Semen is the most important thing in the life cycle of life

PLEASE HELP 50 POINTS!!!!!!!!!!!!!!!

Andrew and Deshawn are teammates on a high school soccer team. They’ve been playing soccer together for years. They both play the center forward position. Some years, Andrew is better than Deshawn and serves as the team’s starter. Other years, Deshawn is the stronger player and gets the most playing time. They are both very competitive with each other. Although they know each other well, they have never been friends.

In practice yesterday, the team was running drills in the rain. Deshawn slipped in the mud and collided with Andrew. Andrew hurt his knee badly in the fall and will have to sit out for several weeks.

The next day, Andrew told everyone at school that Deshawn hurt him on purpose to get more playing time. Deshawn retaliated by sharing private information about Andrew on social media. Andrew’s best friend Mateo saw the collision. He knows it was a complete accident.

Pick the role of Andrew, Deshawn, or Mateo.
What are the main issues/problems from this person’s perspective?
What ethical issues are involved for this person?
Why are these ethical issues relevant for this person?
How should the person you chose handle the situation?

Answers

Answer:

1. I pick the role of Mateo.

2. The main problems from Mateo's perspective are: He knows that the collision was a complete accident and that Deshawn did not injure Andrew on purpose. Because Andrew told everyone that Deshawn injured him on purpose, Deshawn did something unethical by sharing private information about Andrew on social media.

3. The ethical issues are: Andrew took his hurt and frustration of being injured and missing play time out on Deshawn, so he slandered him by saying that Deshawn hurt him on purpose. Deshawn then retaliated by sharing personal information about Andrew on social media, which is also unethical.

4. These issues are relevant to Mateo because he is Andrew's best friend AND he saw the incident happen and knows it was an accident.

5. If I was Mateo, I would talk to Andrew and explain to him that I know he is mad that he is injured and can't play for several weeks, but telling everyone that Deshawn did it on purpose wasn't right or good sportsmanship. I would encourage Andrew to meet with Deshawn with me and have Andrew apologize to Deshawn for saying it was his fault, and then encourage Andrew to go and tell everyone the real story. I would also encourage Deshawn to apologize for posting private information about Andrew, have Andrew ask him to take it down, and then ask Deshawn to post another post saying why he did it and that he was sorry. I would also encourage them to work together, since they are both star players.

Explanation:

Which shows the correct steps in the formation of an ionic bond between these atoms?

A magnesium atom accepts six electrons from the fluorine atoms → Each fluorine atom donates three of the electrons → The magnesium atom becomes a -2 ion → Each fluorine atom becomes a +1 ion
A magnesium atom donates two electrons to the fluorine atoms → Each fluorine atom accepts one of the electrons → The magnesium atom becomes a -2 ion → Each fluorine atom becomes a +1 ion
A magnesium atom accepts two electrons from the fluorine atoms → Each fluorine atom donates one of the electrons → The magnesium atom becomes a -2 ion → Each fluorine atom becomes a +1 ion
A magnesium atom donates two electrons to the fluorine atoms → Each fluorine atom accepts one of the electrons → The magnesium atom becomes a +2 ion → Each fluorine atom becomes a -1 ion

Answers

Answer:

D) A magnesium atom donates two electrons to the fluorine atoms → Each fluorine atom accepts one of the electrons → The magnesium atom becomes a +2 ion → Each fluorine atom becomes a -1 ion

Explanation:

sorry if its a bit late

The correct steps in the formation of an ionic bond are A magnesium atom donates two electrons to the fluorine atoms → Each fluorine atom accepts one of the electrons → The magnesium atom becomes a +2 ion. The correct option is D.

What are ionic bonds?

The electrical attraction between two ions with opposing charges creates an ionic bond, also known as an electrovalent bond, in a chemical molecule.

Ionic compounds are created by ionic bonds, while covalent bonds create covalent compounds. Ionic bonds are created by a complete transfer of electrons, whereas covalent bonds are created by sharing electrons.

Covalent bonds are weaker than ionic ones. Ionic compounds have higher melting and boiling points.

Therefore, the correct option is D.

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An Astronaut on the Moon drops a rock straight downward from a height of 1.25 meters. If the acceleration of gravity on the Moon is 1.62 meters per second squared, what is the speed of the rock just before it lands?

Answers

Answer:

Since the astronaut drops the rock, the initial velocity of the rock is 0 m/s

We are given:

initial velocity (u) = 0 m/s

final velocity (v) = v m/s

acceleration (a) = 1.62 m/s/s

height (h) = 1.25 m

Solving for v:

From the third equation of motion:

v²-u² = 2ah

replacing the variables

v² - (0)² =2 (1.62)(1.25)

v² = 1.62 * 2.5

v² = 4 (approx)

v = √4

v = 2 m/s

The speed of the rock just before it lands is 2 m/s

A cylinder of mass 250 kg and radius 2.60 m is rotating at 4.00 rad/s on a frictionless.
Two more identical nonrotating cylinders fall on top of the first. Because of friction
between the cylinders they will eventually all come to rotate at the same rate. What is this final angular velocity?​

Answers

Answer:

The angular momentum of a cylinder, when it is rotating with constant angular velocity is Lini =Iωi

. When two cylinders are added to the rotating cylinder, which are identical in their dimensions, the moment of inertia of the entire system increases (since mass increases). The final moment of inertia will be 3I

Since friction exist, all the cylinders start rotating with same angular velocity, the new angular velocity can be calculated using conservation of angular momentum

Thus, Iωi =3Iωf ⟹ωf =ωi/3 = 0.33ωi

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