Which technological advancement made the Pony Express unnecessary?
Steamships
Cotton Gin
Telegraph
Steel Plow
Answer: Option (C) is correct, Telegraph
Explanation: Hope it helps!
Good luck!!!
An model leans off a bridge railing to take a picture and accidentally drops their phone. The phone's mass is 0.115 kg and the bridge is 15 m tall. The instant the model dropped the phone, it's mechanical energy is 16.9 joules? why?
Answer:
The statement is true:
Explanation:
As said in the statement, we need to measure the mechanical energy(M.E) of the phone at the instant is dropped:
M.E = P.E + K.E
Given the fall hasn't yet begun, the kinetic energy (K.E) is equal to zero so M.E = P.E
We must use the Potential Energy formula :
P.E = h x m x g
We know that g is equal to 9.8 [tex]J.kg^{-1} .m^{-1}[/tex] on Earth, the height is 15m and m is 0.115:
M.E = 15 x 0.115 x 9.8 = 16.9 Joules
I'd like some help in these two questions please, thankyou so much. have a great day! stay safe and stay happy. (there are two parts of one question so uh yea.
Answer:
The resultant force is 25 N in the negative x-direction.
Explanation:
We need to find the total force in the x and y-direction and then the resultant force will be the magnitude of the sum of Fx and Fy.
Total force in the x-direction:
[tex]F_{x}=12-37=-25\: N[/tex]
Total force in the y-direction:
[tex]F_{y}=10-10=0\: N[/tex]
Therefore, the magnitude of the resultant force will be:
[tex]F_{R}=\sqrt{F_{x}^{2}+F_{y}^{2}}[/tex]
[tex]F_{R}=\sqrt{(-25)^{2}+0}[/tex]
[tex]|F_{R}|=25\: N[/tex]
The resultant force is 25 N in the negative x-direction, in other words, the car will move to the left.
I hope it helps you!
If more waves pass a point in a given time frame, what does this mean?
A. The frequency has increased, B. The frequency has decreased, C. The speed has decreased, or D. The wavelength has increased?
Answer:
D or A
Explanation:
As Frequency's increases the Wavelength's shorten
The hardest mineral known to people is:
slate
granite
diamond
quartz
Answer:
The hardest mineral known to people is Diamond
If two waves interact in destructive interference, which of the following will be true regarding the new wave formed?
A. The new wave will produce a lower-pitched sound than the two original waves.
B. The new wave will produce a quieter sound than the two original waves.
C. The new wave will produce a higher-pitched sound than the two original waves.
D. The new wave will produce a louder sound than the two original waves.
Help plz
Answer:
b
Explanation:
I need help with question ii) Calculate the speed of these radio waves.
I don't know if I started it right.... I need help plss!!!
Answer:
Speed = Wavelength x Wave Frequency. In this equation, wavelength is measured in meters and frequency is measured in hertz (Hz), or number of waves per second. Therefore, wave speed is given in meters per second, which is the SI unit for speed.
Based on Newton’s 3rd Law of motion, if an archer shoots an arrow at the target, the action force is the bowstring against the arrow. Explain where the reaction force can be found.
Answer:
maybe target, not sure.
Based on Newton’s 3rd Law of motion, if an archer shoots an arrow at the target, the action force is the bowstring against the arrow. Explain where the reaction force can be found.
Answer:
the reaction force is the arrows push against the bow sting
Explanation:
the two objects must react the same , bowstring and arrow.
Answer:
the reaction force is the arrows push against the bow sting
the two objects must react the same , bowstring and arrow.
Two girls are pulling on opposite ends of a thick rope. Both girls are pulling
on the rope with the same force but in opposite directions. If both girls
continue to pull with the same force, what will MOST likely happen? *
a. One girl will pull the other toward her
b. Both girls will stay in the same place
c. Gravity will cause the rope to sag
d. The rope will break
Answer:
B
Explanation:
It the same amount of force is being used it will cancel each other out.
what are two roles of bacteria in a nitrogen cycle
Answer:Nitrogen-fixing bacteria convert free nitrogen gas into nitrogen compounds. ... Bacterias that are decomposers recycle nitrogen compounds in the soil by breaking down animal wastes and dead plants and animals. 3. Other bacteria break down nitrogen compounds and release free nitrogen back into the air.
Explanation:
"The nitrogen fixing and bacteria of decay" is the two major role of bacteria in nitrogen cycle."
What is nitrogen fixing?Nitrogen fixing can be define as the process in which It is possible to see nitrogen converting to nitrate.
What is bacteria of decay?Bacteria of decay can be define as the process in which it is possible to see nitrogen waste converting to ammonia.
What is nitrogen?Nitrogen can be referred as element which is kept in boron family in the periodic table.
Therefore, the two role of bacteria in a nitrogen cycle is bacteria of decay and nitrogen fixing.
To know more about nitrogen fixing click here.
https://brainly.com/question/1615727.
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PLEASE HELP ASAP
Describe the structure of the inner core? The inner core is made of no solid rocks. The inner core is made of liquid metal. The inner core contains melted rocks. The inner core is made of solid iron and nickel.
Answer:
The inner core is a hot, dense ball of (mostly) iron. It has a radius of about 1,220 kilometers (758 miles). Temperature in the inner core is about 5,200° Celsius (9,392° Fahrenheit). The pressure is nearly 3.6 million atmosphere (atm)
Can you help me? Thanks! 10+ points!
Explanation:
velocity: average velocity equals Displacement /change in time.
Kinetic energy: K=1/2mv^2 (m = Mass) ( v = Velocity).
speed using the kinetic energy is also KE =1/2mv^2
(M in Kg) (V in m/s)
A campfire could be called.
Answer:
a fire at campsite that provides light and warmth.
As human activities constantly change the ecosystem, scientists work to find ways to keep ecosystems healthy and intact. In what ways do humans protect and restore the ecosystem? Choose the three that apply.
A.
by providing cultural services
B.
through ecological restoration
C.
by maintaining current conditions
D.
through conservation
E.
by working toward sustainability to maintain diversity
In what ways do humans protect and restore the ecosystem? Choose the three that apply.
B. through ecological restoration
D. through conservation
E. by working toward sustainability to maintain diversity.
Which of the following statements is true regarding the constructive interference diagram shown below? Select all that apply.
A. The amplitude of the wave is increased.
B. During interference, the wave will produce a louder sound.
C. The amplitude of the wave is decreased.
D. The crests of two waves are overlapping.
E. The troughs of the two waves are overlapping.
There is more than one answer. Help plz
The statement i.e. true with respect to the constructive interference diagram should be that the two waves should be overlapped.
What is the constructive interference?At the time when two waves of the same kind of wavelength should be in phase so they created the new wave along with the amplitude that should be equivalent to the sum of the inidvidual amplitudes so this we called as the constructive interference
As per the given diagram, we can say that the crest for two waves that should be overlapped should be considered.
Learn more about wave here: https://brainly.com/question/22157656
Which of the following is an example of a valid experiment?Adding Minutes to different types of soda and recording/comparing the reaction height.Asking your friends what kind of candy they like and recording the responses.Building a baking soda volcano
Asking your friends what kind of candy they like and recording the responses.
recording answers are a valid experiment. but at the same time adding minutes to different types of soda and recording is another great idea.
Statement A is correct. Adding Minutes to different types of soda and recording/comparing the reaction height is an example of a valid experiment.
What is an experiment?An experiment is a technique used to prove or disprove a theory, or to test the efficacy or probability of something that has never been done before.
Experiments reveal cause-and-effect relationships by illustrating what happens when a specific component is changed. Experiments have a wide range of goals and scales,
but they always rely on a repeatable technique and rational interpretation of the outcomes. Natural experimental research is also available.
Adding Minutes to different types of soda and recording/comparing the reaction height is an example of a valid experiment.
Hence statement A is correct.
To learn more about the experiment refer to the link;
https://brainly.com/question/9199868
A glass rod is rubbed briefly with silk and the rod becomes able to attract and lift a number of small pieces of paper. If the rod is rubbed with silk for a longer period of time, explain what will happen and why.
QUICKLY PLEASE!
Answer:
it will have a stronger attraction force
Explanation:
If the rod is rubbed with silk for a longer period of time, then it attract large number of small pieces of paper.
When A glass rod is rubbed briefly with silk, then glass rod is heated because of rod become positively charged. That positively charged glass rod attracts the uncharged pieces of paper because some of the electrons present in the paper accumulate at the end near the rod.Learn more:
https://brainly.com/question/13822373
The gravity of Earth is attracting a person towards the center with 500N of gravitational force. The person is exerting a reactionary force on the Earth with how much force? Explain your thinking behind this.
Answer:
I don't know.
Explanation:
Based on Newton’s 3rd Law of motion, if a baseball player hits a ball with the bat, the action force is the impact of the bat against the ball. Explain where the reaction force can be found.
Answer:
the reaction force will be found where the bat hits the ball.
Explanation:
Answer:
reaction force will be found where the bat hits the ball
Explanation:
An auto company technician is trying to relate a car’s damage in a crash test to the kinetic energy of the car on impact. In addition to the mass of the car, what ratio will the technician need in order to determine to complete his study? The ratio of time to speed, weight to mass, distance to time, or acceleration to speed. Explain why.
Answer:
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Explanation:
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for can anybody help me today
Answer:
hey tyler
Explanation:
Plz help with these 4
What are the characteristics of bones? (list 7)
What role do joints play?
What are the two types of joints?
What are ligaments?
Answer:
1) The human skeleton performs six major functions: support, movement, protection, production of blood cells, storage of minerals, and endocrine regulation. protection of internal organs
2) Joints are where two bones meet. They make the skeleton flexible — without them, movement would be impossible. Joints allow our bodies to move in many ways.
3)A joint is a point where two or more bones meet. There are three main types of joints; Fibrous (immovable), Cartilaginous (partially moveable) and the Synovial (freely moveable) joint
4)A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable.
Explanation:
go-gle your welcome ;)
During an experiment, a scientist places a heat lamp above a bowl of water and uses the lamp to heat up the water. How does heat transfer from the lamp to the water?
Conduction
Convection
Radiation
None of the above
sorry i dont know what subject to put
Answer:
radiation
Explanation:
Which of the following is not true about both scientific laws and scientific theories?
Answer:
In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory. It is a misconception that theories turn into laws with enough research
Explanation:
Energy can't be created or destroyed - Law of Conservation of Energy.
If this is true, where does the mechanical energy go when skateboarding? Eventually the skateboarder will slow down and stop if she doesn't add more mechanical energy by pushing. Choose the most correct statement below.
Energy isn't conserved and actually gets used up.
Mechanical Energy converts into potential energy and then she stops.
Mechanical Energy gets converted into thermal energy through friction.
explain your answer
Answer: Mechanical Energy gets converted into thermal energy through friction
Explanation: when the skateboard is rubbing against whatever it’s rolling on it creates friction which slows down the skateboard, the mechanical energy is then converted into thermal energy. If you’ve ever touched the bottom of a wheel after going fast it typically feels a little warm.
Hope this helped
Explain why this statement is false: "All minerals are rocks." ?
Minerals contain several types of rocks.
Rocks can be made of several minerals.
Minerals are made of elements.
Rocks are bigger than minerals.
Answer:A mineral is a naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties. Common minerals include quartz, feldspar, mica, amphibole, olivine, and calcite.
Explanation:
[]Answer the question below[]
Determine the displacement and distance covered by a man if he walks 10 m north, turns east and walks 20m, and then turns left and walks 10 m.
Give THREE examples of objects that have potential energy
A ball kept on 3rd floor of a building.
A pendulum bob kept at 3m height
A stone thrown vertically upward.
A pressed spring.
A squashed spunge ball.