1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
enyata [817]
2 years ago
15

Newton’s Laws of Motion are absolute in classical physics. One example that uses all three laws simultaneously is the firing of

a rocket in space. Hollywood uses this idea when they use fire extinguishers, or a rocket, in space to move about. Write a brief essay describing how Newton’s Laws explain how a rocket in space can move objects. Be sure to touch on each law within your essay.
Physics
2 answers:
adell [148]2 years ago
8 0

Answer:

I think that by "Classical physics" is meant low speed things. By low speed, I think is meant speed far below very roughly half the speed of light, so that Relativistic, special or general, effects can be ignored. Or at least it is hoped that they can be ignored.

Fire extinguishers and rockets get propelled by forcing out large amounts of material (gases under very high pressure) through a nozzle, and the RECOIL from that propels something forward. So, if the action is the ejection of material, the reaction (recoil) is the ejector moving along the same line in the other direction. And that's an example of Newton's third law.

Given a propulsion system, the magnitude of the force recoiling on the ejector will change the momentum of the ejector, often written as the equation F=ma where F is the force, m is the mass being accelerated, and a being the acceleration.

Just as something will stay still until it is moved - inertia - so once set in uniform motion in a straight line, the thing will continue in that motion, theoretically for ever or until something alters its momentum. Newton's first law is to the effect of "every body continues in a state of rest or uniform motion in a straight line unless acted on by a resultant external force". Which, I think, is where the concept of inertia stems from.

I think that the above mostly  on the 3 laws.Any more help needed, please ask.

Explanation:

reeek

Debora [2.8K]2 years ago
6 0
I think that by "Classical physics" is meant low speed things. By low speed, I think is meant speed far below very roughly half the speed of light, so that Relativistic, special or general, effects can be ignored. Or at least it is hoped that they can be ignored. 
Fire extinguishers and rockets get propelled by forcing out large amounts of material (gases under very high pressure) through a nozzle, and the RECOIL from that propels something forward. So, if the action is the ejection of material, the reaction (recoil) is the ejector moving along the same line in the other direction. And that's an example of Newton's third law. 
Given a propulsion system, the magnitude of the force recoiling on the ejector will change the momentum of the ejector, often written as the equation F=ma where F is the force, m is the mass being accelerated, and a being the acceleration.
Just as something will stay still until it is moved - inertia - so once set in uniform motion in a straight line, the thing will continue in that motion, theoretically for ever or until something alters its momentum. Newton's first law is to the effect of "every body continues in a state of rest or uniform motion in a straight line unless acted on by a resultant external force". Which, I think, is where the concept of inertia stems from. 
I think that the above mostly tcuches on the 3 laws.Any more help needed, please ask.
You might be interested in
You are an engineer helping to design a roller coaster that carries passengers down a steep track and around a vertical loop. Th
vova2212 [387]

Answer:

h >5/2r

Explanation:

This problem involves the application of the concepts of force and the work-energy theorem.

The roller coaster undergoes circular motion when going round the loop. For the rider to stay in contact with the cart at all times, the roller coaster must be moving with a minimum velocity v such that at the top the rider is in a uniform circular motion and does not fall out of the cart. The rider moves around the circle with an acceleration a = v²/r. Where r = radius of the circle.

Vertically two forces are acting on the rider, the weight and normal force of the cart on the rider. The normal force and weight are acting downwards at the top. For the rider not to fall out of the cart at the top, the normal force on the rider must be zero. This brings in a design requirement for the roller coaster to move at a minimum speed such that the cart exerts no force on the rider. This speed occurs when the normal force acting on the rider is zero (only the weight of the rider is acting on the rider)

So from newton's second law of motion,

W – N = mv²/r

N = normal force = 0

W = mg

mg = ma = mv²/r

mg = mv²/r

v²= rg

v = √(rg)

The roller coaster starts from height h. Its potential energy changes as it travels on its course. The potential energy decreases from a value mgh at the height h to mg×2r at the top of the loop. No other force is acting on the roller coaster except the force of gravity which is a conservative force so, energy is conserved. Because energy is conserved the total change in the potential energy of the rider must be at least equal to or greater than the kinetic energy of the rider at the top of the loop

So

ΔPE = ΔKE = 1/2mv²

The height at the roller coaster starts is usually higher than the top of the loop by design. So

ΔPE =mgh - mg×2r = mg(h – 2r)

2r is the vertical distance from the base of the loop to the top of the loop, basically the diameter of the loop.

In order for the roller coaster to move smoothly and not come to a halt at the top of the loop, the ΔPE must be greater than the ΔKE at the top.

So ΔPE > ΔKE at the top. The extra energy moves the rider the loop from the top.

ΔPE > ΔKE

mg(h–2r) > 1/2mv²

g(h–2r) > 1/2(√(rg))²

g(h–2r) > 1/2×rg

h–2r > 1/2×r

h > 2r + 1/2r

h > 5/2r

5 0
3 years ago
Read 2 more answers
Energy needs, in total kilocalories per day, are greater during _____________ than any other time of life.
malfutka [58]
Energy needs, in total kilocalories per day, are greater during adolescence than any other time of life. The correct option among all the options that are given in the question is the second option or option "b". Only during the time of pregnancy will a girl require more kilocalories per day than during the time of adolescence. 
5 0
3 years ago
Read 2 more answers
Why is ice harder than liquid water?
yaroslaw [1]
Hello~ 

Ice is harder than liquid water because<span> the molecules of ice are linked more tightly together than the molecules of liquid water. 

Hope this helps! </span>
6 0
2 years ago
Compare and contrast fluorescent and incandescent light bulbs.
dezoksy [38]

Incandescent light is a glowing white light produced by heat. An incandescent light bulb works by heating a filament in the bulb. Fluorescent light is a bright light produced by electricity flowing through a tube filled with ionized gas. Fluorescent light bulbs are more energy-efficient than incandescent bulbs

5 0
3 years ago
A bike travels 4 miles in half an hour, what is its speed?
omeli [17]

Answer:

8 mph

Explanation:

4 miles in half hour so you add 4 more for the second half

3 0
3 years ago
Other questions:
  • A concentric cylinder viscometer may be formed by rotating the inner member of a pair of closely fitting cylinders (see Fig). Th
    11·1 answer
  • When current flows through an electric motor, the electromagnet rotates. true or false?
    5·1 answer
  • Where do most water molds and downy wildews live?
    15·1 answer
  • Scientists use laser range-finding to measure the distance to the moon with great accuracy. A brief laser pulse is fired at the
    11·1 answer
  • Sound travels fastest through A) space. B) cool air. C) warm air. D) a metal spoon.
    6·2 answers
  • An electronic instrument that measures power and frequency of electronic signals is the
    11·1 answer
  • An object of mass 20g taken at a height of 2m above the ground. Which type of energy is possessed by the object at this height ?
    8·1 answer
  • A heavy book is launched horizontally out a window from the first floor, a height, h, above the ground, with initial velocity, v
    7·1 answer
  • Which force below does the most work? All three displacements are the same. The 10 N force. The 8 N force The 6 N force. They al
    15·1 answer
  • A barometer reads 780 mm Hg. Mercury has a density of 1.36 x 10^4 kg /m^3.
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!