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Everything You Need To Know About Rocket Fuel

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How common has the phrase: ‘it isn’t rocket science’ become and yet when you come to think of it, some of us don’t know much about even fundamentals in the subject. We thought we could take up the topic of rocket fuel and explain as to how it works and what it is made of; read on to learn more.

space-shuttle

What is rocket fuel composed of?

There are two categories of rocket fuel: solids and liquids. While solid rocket fuel mostly uses oxygen in its liquid form along with liquid hydrogen, solid rocket fuels typically make use of powdered aluminium and some sort of an oxidiser. Liquid fuels require cryogenic temperatures for cooling and are often used in rockets that are space bound and solid fuel ones are cheaper and quite easier comparatively when it comes to handling and thus are often used for military purposes. The solid rocket fuel combination is often used for the initial thrust (to give the rocket that extra lift and kick required to head into space).

How does rocket fuel work?

Solid rocket fuels operate on the following principle: a reaction between the components of the fuel that burns very quickly and yet without an explosion. The power in the case of rocket fuels is released evenly and over a period of time and the composition required to achieve this is 72% of nitrates, 24% carbon and 4% sulphur whereas in gun powder where there is an explosion, the ratio is 75:15:10 and explosion is the result there.

The energy required to propel the rocket comes from the oxidation of these chemicals and thus the fundamental is oxidation reaction.

What are the different kinds of fuels used in spacecrafts?

There are a variety of rocket fuels used today from solid fuels, liquid fuels, bio propellants, mono propellants, compressed nitrogen and so on. Quite often, students raise the question of how rocket fuel burns in space without oxygen and how it works in space during classes. In fact, this is perhaps one of the most asked questions to online physics tutors as well.

The answer to that is quite simple. Not every reaction requires oxygen and in some cases liquid oxygen is used as fuel too (Liquid fuels)! Also, as seen above, most rocket fuels carry their own oxidisers and there are some fuels that combust when they react with one another and they contain the oxidisers required. Atmospheric oxygen isn’t relied upon in any case for the rocket fuel to burn.

Watch this space for more such interesting information and get in touch with us for online homework help or online tutoring services.

Learn Everything You Need To Know About The Mirror Formula With An Online Physics Tutor

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Working with physics concepts is not everyone’s cup of tea and especially when it comes to topics such as mirrors whether concave or convex, most students lack the understanding required to work with them. For instance, the mirror formula is quite difficult for most students and often they turn towards online physics tutors to get help with the topic. Read on to learn everything you need to know about the mirror formula and how it is derived.

physics students

Mirror Formula – what is it?

The mirror formula is essentially the relationship between an object (its distance), the image distance and the focal length. For a concave mirror, the formula goes as follows:

f – focal length, u – object distance, v – image distance

1/f = 1/u + 1/v

While we are at it, it is important to learn the sign conventions of spherical mirrors before we proceed with the derivation part.

Sign Conventions and how they are used for Spherical Mirrors

There are three basic assumptions or conventions that one needs to know and they are:

  • Every distance is measured from the pole of the mirror.
  • Any distance that is measured in the direction of the ray of incidence or the incident ray is considered positive and the rays that are in the other direction (Opposite) are considered with a negative sign.
  • Any distance that is measured above the principal axis is deemed positive and below is negative.

The below diagrams represent the conventions mentioned above for both the concave and the convex mirror. concave mirror1

Derivation of the Mirror Formula for a Concave Mirror

This topic often sends students into a dizzy and assignments related to them are considered way too difficult. Learning the derivation properly can in itself serve as the best possible physics assignment help for students seeking to score straight A’s in their assignments. Read on to learn to derive the Mirror Formula. concave mirror2

In the above figure, the object AB is at a distance ‘u’ from the pole of the mirror (marked by ‘P’ in the diagram). Its image is formed at A1B1, a distance of ‘v’ from the pole. In the above figures, angles A1CB1and ACB are vertically opposite and hence equal. Similarly, angles ABC and A1B1C are right angles and hence equal.

angle ACB = angle A1CB1

angle ABC = angle A1B1C = 90 degrees

Thus, the third angle B1A1C and BAC in the two triangles are equal too and thus these two triangles are similar.

As triangles A1B1C and ABC are similar, we can write the following:

AB/ A1B1 = BC/B1C

In the same way, triangles, F B1 A1 and FED are similar. Thus, we can also write the following:

ED/ A1B1 = EF/F B1

It is apparent from the figure that ED and AB are equal. Thus, the above two equations can be simplified as follows:

BC/B1C = EF/F B1

Assuming that D is very close to P and the distance between them is negligible, we can write the above equation as follows (assuming that EF = PF):

BC/B1C = PF/F B1

We now proceed to wrote BC, FB1 and B1C as follows:

BC = PC – PB

B1C = PB1 – PC

F B1 = PB1 – PF

Thus, the above equation can be rewritten as follows:

(PC-PB)/( PB1 – PC) = PF/( PB1 – PF)

PC = R, PB is u and PF is f. V here is represented by PB1

The above equation thus further can be written as follows and with the sign convention, all of them take a negative sign which gives us:

(-R –(-u))/(-v –(-R)) = -f/(-v –(-f))

This gives us the following:

(-R + u) / (-v + R) = -f/(-v+f)

(u-R)/(R-v) = f/(v-f)

Cross multiplying and simplifying on both sides gives us the following:

uv – uf – Rv + Rf = Rf – vf

This further becomes:

uv – uf – Rv -= -vf

Since R = 2f, this can be written as:

uv – uf –2vf = -vf

This further gives us : uv – uf = vf

When you divide the above equation by uvf, you get the mirror formula:

1/f – 1/v = 1/u or alternately, 1/f = 1/u + 1/v.

Summary

Students usually look for physics homework help when it comes to understanding and working with concave and convex mirrors. Learning to derive the mirror formula will help students ace this topic and score high in physics tests.

Summary

Students usually look for physics homework help when it comes to understanding and working with concave and convex mirrors. Learning to derive the mirror formula will help students ace this topic and score high in physics tests.

How To Master The Concept Of Fundamental Forces?

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Every subject has certain fundamental concepts and theories that have to be mastered before a student proceeds to learn advanced concepts. Force is one of the primary things in physics, we can experience it all around us and understanding what it is all about is important to excel in physics. For instance, take the case of how an object accelerates to the ground during free fall or how an object rolls down an inclined plane. These are day to day occurrences that we see around us and physics is the subject that has an explanation for all of this. Let us analyze the theory behind the fundamental forces in physics; read on to learn more.

Fundamental Forces – an overview

There are many different kinds of forces that act on an object while in motion or even when it is resting. However, there are only a few of the fundamental forces and these are also the topics wherein students seek physics homework help online. The fundamental forces are:

  • The Gravitational Force
  • The Electromagnetic Force
  • The Nuclear Force – Strong and Weak

Concept Of Fundamental Forces

Gravitational Force

The force of gravity is something that most of us are familiar with and is explained with Newton’s law. It is simply the force that exists or acts between any objects that posses mass. The center of gravity, Newton’s law of universal gravitation and the theory of relativity are the most studied topics under this head. Most teachers explain this concept by dropping an object to the floor and explaining why the object spirals downwards and how gravitational pull works on the object.

Concept Of Fundamental Forces

Electromagnetism

Whenever particles interact with other particles and both are electrically charged, this phenomenon is referred to as electromagnetism. The electromagnetic force is perhaps the most prevalent and obvious force and citing examples around us is pretty easy and serves to improve learning dramatically. Usually the best online physics tutors employ various experiments and practical demonstrations to teach this important topic to students. Many consider electric and magnetic forces to be distinctly different and only when students lean this concept do they understand as to how they are interlinked.

Nuclear Force

The forces that act inside an atom are equally important and they are one of the fundamental forces there are. There are two kinds of nuclear forces: the strong and the weak nuclear force. The strong force is responsible for the binding of the protons and neutrons within the nucleus while the weak force is responsible for things such as beta decay and so on. These are studies extensively in atomic and nuclear physics. This is perhaps one of the toughest concepts for students when it comes to fundamental forces and thus most of them seek physics assignment help and homework help online for this topic.

Summary

The fundamental forces in physics are responsible for most of the phenomena we see around us day to day. The four fundamental types of interactions described above are responsible for most of the interactions observed and they can be completed described by these fundamental forces. Learning this concept well is important if a student aspires to get into a physics based major or aspires to be a scientist.