Q.1
Fill in the blanks
i.
NOT any force moves
something away from you.
ii.
Along folded tubes in the abdomen which absorbs nutrients is called Small
Intestine.
iii.
The place where waste is stored before it leaves the body is called rectum
iv.
The part of the food which is not digested Fiber.
v.
The part of digestive system in which conversion of starch to sugar starts is the
mouth
vi.
The finger like structures which absorbs nutrient are called villi.
vii.
Plasma contains 90 percent water.
viii.
RBCs contain a pigment called Haemoglobin.
ix.
A turning fork produces a sound wave in air with frequency of 250 Hz Wavelength
will be 250 when speed of sound is 450 m/sec.
x.
The value of K.E for the date: m=5kg, v=3m/s2 will be 22.2 joule.
Q.2
Describe law of conservation of energy.
Answer
All the forms of
energy follow the law of conservation of energy. In brief, the law of
conservation of energy states that In a closed system, i.e., a system that is
isolated from its surroundings, the total energy of the system is conserved.
In physics and chemistry,
the law of conservation of energy states that the total energy of
an isolated system remains
constant; it is said to be conserved over
time. This law, first proposed and tested by Émilie du Châtelet, means that energy can
neither be created nor destroyed; rather, it can only be transformed or
transferred from one form to another. For instance, chemical
energy is converted to kinetic
energy when a stick of dynamite explodes.
If one adds up all forms of energy that were released in the explosion, such as
the kinetic energy and potential
energy of the pieces, as well as heat and sound,
one will get the exact decrease of chemical energy in the combustion of the
dynamite.
Classically, conservation of energy was
distinct from conservation of mass;
however, special relativity showed
that mass is related to energy and vice versa by E = mc2, and
science now takes the view that mass-energy as a whole is conserved.
Theoretically, this implies that any object with mass can itself be converted
to pure energy, and vice versa. However this is believed to be possible only
under the most extreme of physical conditions, such as likely existed in the
universe very shortly after the Big Bang or
when black holes emit Hawking
radiation.
Conservation of energy can be rigorously proven
by Noether's theorem as a consequence of continuous time translation symmetry; that
is, from the fact that the laws of physics do not change over time.
A consequence of the law of conservation of
energy is that a perpetual motion machine of the first kind cannot
exist, that is to say, no system without an external energy supply can deliver
an unlimited amount of energy to its surroundings. For systems which do
not have time translation symmetry, it may
not be possible to define conservation of energy. Examples include curved
spacetimes in general relativityor time
crystals in condensed matter physics.
Ancient philosophers as
far back as Thales
of Miletus c. 550 BCE had inklings of the
conservation of some underlying substance of which everything is made. However,
there is no particular reason to identify their theories with what we know
today as "mass-energy" (for example, Thales thought it was
water). Empedocles (490–430 BCE) wrote that in his universal
system, composed of four
roots (earth, air, water, fire), "nothing
comes to be or perishes";instead, these elements suffer continual
rearrangement. Epicurus (c. 350
BCE) on the other hand believed everything in the universe to be composed of
indivisible units of matter—the ancient precursor to 'atoms'—and he too had
some idea of the necessity of conservation, stating that "the sum total of
things was always such as it is now, and such it will ever remain."
In 1605, Simon
Stevinus was able to solve a number of problems in
statics based on the principle that perpetual
motion was impossible.
In 1639, Galileo published
his analysis of several situations—including the celebrated "interrupted
pendulum"—which can be described (in modern language) as conservatively
converting potential energy to kinetic energy and back again. Essentially, he
pointed out that the height a moving body rises is equal to the height from
which it falls, and used this observation to infer the idea of inertia. The
remarkable aspect of this observation is that the height to which a moving body
ascends on a frictionless surface does not depend on the shape of the surface.
In 1669, Christiaan Huygens published
his laws of collision. Among the quantities he listed as being invariant before
and after the collision of bodies were both the sum of their linear
momenta as well as the sum of their kinetic
energies. However, the difference between elastic and inelastic collision was
not understood at the time. This led to the dispute among later researchers as
to which of these conserved quantities was the more fundamental. In his Horologium Oscillatorium, he
gave a much clearer statement regarding the height of ascent of a moving body,
and connected this idea with the impossibility of perpetual motion. Huygens'
study of the dynamics of pendulum motion was based on a single principle: that
the center of gravity of a heavy object cannot lift itself.
It was
Leibniz during 1676–1689 who first attempted a mathematical formulation of the
kind of energy that is associated with motion (kinetic energy). Using
Huygens' work on collision, Leibniz noticed that in many mechanical systems (of
several masses, mi each
with velocity vi),
was
conserved so long as the masses did not interact. He called this quantity
the vis viva or living force of the system.
The principle represents an accurate statement of the approximate conservation
of kinetic energy in
situations where there is no friction. Many physicists at
that time, such as Newton, held that the conservation of momentum, which
holds even in systems with friction, as defined by the momentum:
was the
conserved vis viva. It was later shown that both quantities are conserved
simultaneously, given the proper conditions such as in an elastic
collision.
In
1687, Isaac Newton published his Principia, which was organized around the concept of
force and momentum. However, the researchers were quick to recognize that the
principles set out in the book, while fine for point masses, were not
sufficient to tackle the motions of rigid and fluid bodies. Some other
principles were also required.
The law
of conservation of vis viva was championed by the father and son duo, Johann and Daniel
Bernoulli. The former enunciated the principle of virtual
work as
used in statics in its full generality in 1715, while the latter based
his Hydrodynamica, published in 1738, on this single conservation
principle. Daniel's study of loss of vis viva of flowing water led him to
formulate the Bernoulli's principle, which
asserts the loss to be proportional to the change in hydrodynamic pressure.
Daniel also formulated the notion of work and
efficiency for hydraulic machines; and he gave a kinetic theory of
gases, and linked the kinetic energy of gas molecules with the temperature of
the gas.
This
focus on the vis viva by the continental physicists eventually led to the
discovery of stationarity principles governing mechanics, such as the D'Alembert's principle, Lagrangian, and Hamiltonian formulations of mechanics.
Émilie du Châtelet (1706–1749)
proposed and tested the hypothesis of the conservation of total energy, as
distinct from momentum. Inspired by the theories of Gottfried Leibniz, she
repeated and publicized an experiment originally devised by Willem 's Gravesande in
Q.3
State Coulombs law. Derive relation of charges with attractive force.
Answer
Colomb’s law states
that the magnitude of the electrostatic force of attraction or repulsion
between two electrically charged bodies is directly proportional to the product
of the charge of the charged bodies and inversely proportional to the square of the
distance between the center of the charged bodies.
Coulomb's law, or Coulomb's inverse-square law,
is an experimental law[1] of physics that
quantifies the amount of force between two stationary, electrically
charged particles. The electric force between
charged bodies at rest is conventionally called electrostatic
force or Coulomb force. Although the law was known
earlier, it was first published in 1785 by French physicist Charles-Augustin de Coulomb, hence
the name. Coulomb's law was essential to the development of the theory of electromagnetism, maybe
even its starting point, as it made it possible to discuss the quantity of
electric charge in a meaningful way.
The law states that the magnitude of the electrostatic force of attraction or repulsion between two
point charges is directly proportional to the product
of the magnitudes of charges and inversely proportional to the square of the
distance between them,[4]
Here, K or ke is Coulomb's constant (ke ≈ 8.988×109 N⋅m2⋅C−2),[1] q1 and q2 are
the signed magnitudes of the charges, and the scalar r is the
distance between the charges.
The force is along the straight line joining
the two charges. If the charges have the same sign, the electrostatic force
between them is repulsive; if they have different signs, the force between them
is attractive.
Being an inverse-square law, the
law is analogous to Isaac
Newton's inverse-square law of universal gravitation, but
gravitational forces are always attractive, while electrostatic forces can be
attractive or repulsive.[2] Coulomb's
law can be used to derive Gauss's
law, and
vice versa. In the case of a single stationary point charge, the two laws are
equivalent, expressing the same physical law in different ways.[5] The
law has been tested extensively, and
observations have upheld the law on the scale from 10−16 m to
108 m.[
Coulomb’s law
states that the force between two static point electric charges is proportional
to the inverse square of the distance between them, acting in the direction of
a line connecting them. If the charges are of opposite sign,
the force is attractive and if the charges are of the same sign, the force is
repulsive.
Coulomb’s
law is often one of the first quantitative laws encountered by students of
electromagnetism. It describes the force between two point electric charges. It
turns out that it is equivalent to Gauss’s law. Coulomb’s law states that the
force between two static point electric charges is proportional to the inverse
square of the distance between them, acting in the direction of a line
connecting them. If the charges are of opposite sign, the force is attractive
and if the charges are of the same sign, the force is repulsive.
Mathematically, Coulomb’s law is written as
(43)ÁF=qQ4πε0|r−r′|2 r―^,
where F is
the force between the two charges q and Q, |r−r′| is
the distance between the charges and r―^ is
a unit vector in the direction of the line separating the two charges.
Having
defined Coulomb’s law, one might next naturally ask the question how would a
standard reference charge behave in the presence of any distribution of
electric charge we might dream up? Answering this question brings us to the
concept of the electric field. We follow the presentation of [Gri99]. We can
define the electric field of an arbitrary charge Q as
the force experienced by a unit charge q due
to Q
(44)Áe=Fq.
Dividing
both sides of Coulomb’s law by q and
substituting the definition of e, we
get that the electric field of a point charge Q is
(45)Áe(r)=Q4πε0|r−r′|2 r―^.
It
is important to note here that the electric field obeys the principle of
superposition, meaning that the electric field of an arbitrary collection of
point charges is equal to the sum of the electric fields due to each individual
charge.
Q.4
Write characteristics features of phylum Echinodermata and Chordata.
Answer
The organisms belonging to the phylum
Echinodermata are exclusively marine. Till date, there have been no traces of
any terrestrial or freshwater Echinoderms.
These are multicellular organisms with
well-developed organ systems. All the animals belonging to this phylum share
the same characteristics features. They are colourful organisms with unique
shapes. They are ecologically and geologically very important.
The Echinoderms are found in sea-depths as well
as in the intertidal zones. An interesting feature of the phylum Echinodermata
is that all the organisms belonging to this phylum are marine. None of the
organisms is freshwater or marine.
The water vascular system present in
echinoderms accounts for gaseous exchange, circulation of nutrients and waste
elimination.
Characteristics of
Echinodermata
1. They
have a star-like appearance and are spherical or elongated.
2. They are
exclusively marine animals.
3. The
organisms are spiny-skinned.
4. They
exhibit organ system level of organization. Most members have a circulatory
system as well as a digestive system.
5. They are
triploblastic and have a coelomic cavity.
6. The
skeleton is made up of calcium carbonate.
7. They
have an open circulatory system.
8. They
respire through gills or cloacal respiratory tree.
9. They
have a simple radial nervous system and the excretory system are absent.
10. The body
is unsegmented with no distinct head. The mouth is present on the ventral side
while the anus is on the dorsal side.
11. The tube
feet aids in locomotion.
12. They
reproduce sexually through gametic fusion and asexually through
regeneration. Fertilization is
external.
13. The
development is indirect.
14. They
possess the power of regeneration.
15. They
have poorly developed sense organs. These include chemoreceptors, tactile
organs, terminal tentacles, etc.
Classification of
Echinodermata
Asteroidea
·
They have a flattened, star-shaped body with five
arms.
·
They have tube feet with suckers.
·
They respire through papulae.
·
The body comprises of calcareous plates and
movable spines.
·
Pedicellaria is present.
·
Eg., Asterias, Zoroaster
Ophiuroidea
·
The body is flat with pentamerous discs.
·
The tube feet are devoid of suckers.
·
They respire through Bursae.
·
The long arms are demarcated from the central
disc.
·
Eg., Ophiderma, Amphuria
Echinoidea
·
The body is hemispherical.
·
The tube feet contains suckers.
·
The body does not have arms.
·
The body has a compact skeleton and movable
spines.
·
Eg., Echinus, Cidaris
Holothuroidea
·
The body is long and cylindrical.
·
The arms, spines, and pedicellariae are absent.
·
They respire through the cloacal respiratory
tree.
·
They possess tube feet with suckers.
·
Eg., Cucumaria, Holothuria
Crinoidea
·
The body is star-shaped.
·
The tube feet have no suckers.
·
The arms are bifurcated.
·
Spines and pedicellariae are absent.
·
Eg., Neometra, Antedon
Q.5
Write disorders of heart and lungs. Give suggestions to avoid these diseases.
Answer
Pulmonary Vascular Disease Pulmonary vascular disease (PVD) is a broad term
including any condition that affects the blood vessels within the lungs. These
vessels take blood that is depleted of oxygen to the lungs from the right side
of the heart. Deoxygenated blood travels through the pulmonary arteries where
oxygen is taken up.
Pulmonary
vascular disease (PVD) is a broad term including any condition that affects the
blood vessels within the lungs. These vessels take blood that is depleted of
oxygen to the lungs from the right side of the heart. Deoxygenated blood
travels through the pulmonary arteries where oxygen is taken up. The pulmonary
veins leave the lungs and take blood rich with oxygen to the left side of the
heart where oxygenated blood is distributed throughout the body. This process
continually replenishes the blood with oxygen, and lets carbon dioxide be
exhaled. A pulmonary vascular disorder can lead to cardiovascular problems as
well as impairing the quality of the patient’s life.
The Pulmonary Vascular Disease Program—a collaborative venture between the Brigham and Women’s Hospital
Lung Center and the Heart & Vascular Center—offers personalized care and
coordinated management for all types of PVD, including pulmonary arterial
hypertension, right heart failure, and chronic thromboembolic pulmonary
hypertension (CTEPH). Our pulmonologists and cardiologists work closely
together. This expertise and collaboration helps patients manage symptoms and
have an improved quality of life. The research on PVD which is conducted at the
Brigham provides greater understanding of these diseases and is translated
directly into exceptional patient care.
The
only definitive treatment is lung transplantation.
What
are the causes of pulmonary vascular disease?
The
causes of pulmonary vascular disease vary according to which of the lungs’
blood vessels are affected.
How
is pulmonary vascular disease diagnosed?
In
addition to taking a full medical history, your physician will conduct a
variety of tests to diagnose PVD, as well as determine the specific disorder.
These
tests can include:
Right
Heart Catheterization and Vasodilator Testing
What
is the treatment for pulmonary vascular disease?
In
treating PVD, your physician aims to lessen the severity of symptoms, which
will help improve your quality of life. This will also lessen the strain on
your heart and decrease your risk for heart failure. You and your healthcare
team will develop a personalized plan (based on your specific condition, age,
and other factors) that may include a variety of medications and surgery.
What
can I expect?
When
you become a patient, our team of experts develops a personalized,
multidisciplinary care plan based on your specific condition. Our Pulmonary Vascular Disease Program provides long-term care and support to help patients manage
their disease. We emphasize patient education, give patients access to research
opportunities and offer a support group for patients and families to share
personal experiences.
TEAM-BASED CARE
The Pulmonary Vascular Disease Program—joint venture between the Brigham and Women’s Hospital Lung Center
and the Heart & Vascular Center—offers highly specialized,
multidisciplinary evaluation and care for patients with complex pulmonary
vascular conditions. Our pulmonologists and cardiologists, work closely
together and with cardiac and thoracic surgeons, and other cardiovascular
specialists.