SOLUTION

If G is considered  to be 1 unit       then W= 10²⁵ units              E = 10³⁶ units                     N = 10³⁹ units       hence the order is G  

SOLUTION

Einstein’s mass-energy equivalence relation is E = mc² According to Einstein a mass m is equivalent to energy mc² has led to the unification of the two laws i.e. law of conservation of mass and energy.

SOLUTION

Isotropy means uniformity in all orientations.

SOLUTION

The nuclear force between the nucleons exists only when they are inside the nucleus and hence it is a short range force.

SOLUTION

Isaac Newton unified terrestrial and celestial mechanics in 1687.

SOLUTION

Robert Hook

SOLUTION

In 1998 Hahn and Meitner discovered the phenomenon of neutron induced fission of uranium

SOLUTION

Laser

SOLUTION

In Physics, attempts have been made to explain diverse physical phenomena in terms of a few concepts and laws. The effort is to see the physical world as manifestation of some universal laws in different domains and conditions. The attempts to unify fundamental forces of nature reflect the same quest for unification.

SOLUTION

According to Einstein’s theory, mass m is equivalent to energy E given by the relation E= mc², where c is speed of light in vacuum.

SOLUTION

This statement can be best explained with this example - the free fall of an object under gravity. Both the kinetic energy of the object and its potential energy change continuously with time, but the sum remains fixed. If the object is released from rest, the initial potential energy is completely converted into the kinetic energy of the object just before it hits the ground.

SOLUTION

Matter consists of elementary charged constituents like electrons and protons. Since the electromagnetic force is so much stronger than the gravitational force, it dominates all phenomena at atomic and molecular scales. The other two forces, i.e., weak forces and nuclear forces, operate only at nuclear scales. Thus it is mainly the electromagnetic force that governs the structure of atoms and molecules, the dynamics of chemical reactions and the mechanical, thermal and other properties of materials.

SOLUTION

Classical and Newtonian Physics deal mainly with macroscopic phenomena and is inadequate to handle macroscopic domain. Quantum physics, on the other hand, deals with the microscopic domain of physics at the minute scales of atoms and nuclei.

SOLUTION

Attempts have been made to derive the properties of a bigger, more complex, system from the properties and interactions of its constituent simpler parts. This approach is called reductionism.

SOLUTION

The result of experiment of scattering of alpha particles by gold foil, by Ernest Rutherford established the nuclear model of the atom. It was concluded that there is a massive centre consisting of protons and neutrons and it is surrounded by electrons. The massive centre is known as the nucleus of the atom.

SOLUTION

Nuclear forces have a range of 10^-15 m. Gravitational and electromagnetic forces have infinite range.

SOLUTION

Ernest Lawrence thought about making a compact accelerator that produced high energy particles. He made one with a circular accelerating chamber between the poles of an electromagnet, which came to be known as cyclotron.

SOLUTION

Edwin Hubble is known for showing that the recessional velocity of a galaxy increases with its distance from the earth, which implies that the Universe is expanding.

SOLUTION

Homi J. Bhabha was born in India on October 30, 1909.

SOLUTION

Michelson was born in Strzelno, Prussian Partition of Poland in 1852. He moved to US in 1855 with his parents.

SOLUTION

Rutherford's alpha-ray scattering experiment led to the discovery of atomic nucleus, which led him to postulate the Nuclear model of atom.

SOLUTION

An atom has proton, electron, and neutron only

SOLUTION

British physicist, J.J. Thomson discovered electron in 1897.

SOLUTION

C.V. Raman won the Nobel prize in 1930 for the discovery of Raman effect.

SOLUTION

force                          relative strength gravitational force                    1 weak nuclear force                  10²⁵ electromagnetic force              10³⁶ strong nuclear forces               10³⁸

SOLUTION

When light of suitable frequency falls on the emitter of a photocell, it emits electrons on account of photoelectric effect.

SOLUTION

Salam, Glashow and Weinberg showed in 1979 that the weak nuclear force and the electromagnetic force can be viewed as different aspects of a single electro-weak force.

SOLUTION

Albert Einstein gave the special theory of relativity and theory of general relativity.

SOLUTION

A hypothesis is an educated guess can either be right or wrong. It has to be tested and proved true, to become a theory.

SOLUTION

Newton’s laws are axiomatic and can be proved by using logical or mathematical approach. We can easily observe and provide daily life examples to justify the statements of Newton’s laws. However, the universal law of gravitation is a hypothesis, as we cannot prove it using daily life examples.

SOLUTION

James Chadwick discovered neutron in1932.

SOLUTION

Electromagnetic forces are central forces because they act along the line joining the charged particles.

SOLUTION

According to law of conservation of momentum, in the absence of an external force, the total momentum of a system remains unchanged. Thus, we can find out the initial momentum of the gun and the bullet before firing and then final momentum after firing. Equating theses two, we can find out the recoil velocity of the gun.

SOLUTION

Optic fibres are used in television. It transmits signals from one place to another by means of total internal reflection of light.

SOLUTION

In a chemical reaction, if the total binding energy of the reacting molecules is greater than the total binding energy of the product molecules, the difference is absorbed from the surroundings and the reaction is endothermic.

SOLUTION

In a chemical reaction, if the total binding energy of the reacting molecules is less than the total binding energy of the product molecules, the difference appears as heat and the reaction is exothermic.

SOLUTION

Isotropy of space signifies that there is no preferred particular direction in space. Hence, it underlies the conservation of angular momentum.

SOLUTION

In a nuclear process mass gets converted to energy (or vice-versa). The energy, which is released in a nuclear power generation and nuclear explosions is converted from the mass of the nuclear reactants. An electron and its antiparticle positron can be created from energy (photons).

SOLUTION

The total linear momentum and the total angular momentum of an isolated system are also conserved quantities and both are vectors.

SOLUTION

Energy is a scalar quantity and is a conserved quantity. But all conserved quantities are not necessarily scalars. The total linear momentum and the total angular momentum of an isolated system are also conserved quantities and both are vectors.

SOLUTION

The strong nuclear force is the strongest, then comes the electromagnetic force. And the gravitational force is the weakest force. Hence, the weak nuclear force is not as weak as the gravitational force, but much weaker than the strong nuclear and electromagnetic forces.

SOLUTION

Protons and neutrons are built out of still more elementary constituents called quarks. Quarks-Quark force build the universe which caused by the exchnage of particles called gluons is the basic force.

SOLUTION

A nucleus will be unstable only if the electric repulsion between its protons is overcome by some attractive force. This attractive force cannot be gravitational since force of gravity is negligible compared to the electric force. So, this force can be the strong nuclear force, which is the strongest of all fundamental forces. Hence, the net force existing between two protons in a nucleus is attractive.

SOLUTION

The strong nuclear force binds protons and neutrons in a nucleus. It is charge-independent and acts equally between a proton and a proton, a neutron and a neutron, and a proton and a neutron.

SOLUTION

The atoms in atmosphere are ionized during the collisions of clouds leading to the production of charged particles. Then electric forces come into play leading to lightning.

SOLUTION

Matter is mostly, electrically neutral (net charge is zero). Thus, electric force is largely zero and gravitational force dominates terrestrial phenomena. The other two forces, i.e., weak forces and nuclear forces, operate only at nuclear scales.

SOLUTION

Gravity is always attractive because mass comes only in one variety, i.e., there is no negative mass. However, had there been negative masses, gravitational forces would have been either attractive or repulsive as in the case of electric forces where both positive and negative charges exist.

SOLUTION

Like the gravitational force, electromagnetic force acts over large distances and does not need any intervening medium. It is enormously strong compared to gravity. The electric force between two protons, for example, is 1036 times the gravitational force between them, for any fixed distance. Since, the mass of the earth is very much greater than that of the moon, its gravitational force is greater.

SOLUTION

H. yukawa

SOLUTION

Christiaan Huygens

SOLUTION

Geology.

SOLUTION

Optical fibres work on the principle of total internal reflection of light.

SOLUTION

The elastic spring forces arise due to the net attraction / repulsion between the molecules of a spring.

SOLUTION

Physics has been taken from Greek word which means nature. Actually many events are taking place in nature in accordance with some basic laws. To reveal those laws with observed events is physics.

SOLUTION

Technological development is closely related to the application of physics. Developed societies always have advanced technologies .Technologists use this information for designing the various appliances and other instruments which help in advancement of physics.

SOLUTION

Physics has great impact on society .The discoveries and developments in physics have changed the face of society. Now we have better lifestyle which is because of the inventions in physics like television, radio, and aeroplane.

SOLUTION

There are mainly four types of forces in nature:  

1.      Gravitational force

2.      Nuclear force

3.      Electromagnetic force

4.      Weak force

SOLUTION

Four physical devices are given as follows:  

1. X-Rays tube
2. Electromagnetic resonator (EMR)
3. Stethoscope.
4. Ultrasound machine
   

SOLUTION

It is defined as the study of newest techniques for producing machines, gadgets e.t.c., by using scientific discoveries and advancements. 

SOLUTION

The war time application of physics are:
1. Bombs.
2.Nuclear weapons.
3.Jet fighters.
4.Bombers,missile.
5.Transportation and electronic devices.

SOLUTION

The maritime applications of physics are,
1.Navigation of ships, tankers and aeroplanes.
2.Television.
3.Radio.
4.Music System.

SOLUTION

Physics is called exact science because it involves the accurate measurement of all physical quantities involved.

SOLUTION

Some of the famous German Physicists are given as follows:  

1.WK Roentgen for: X-Rays.

2.Albert Einstien for: Theory of relativity.

3.H.R Hertz for: Theory of electromagnetic waves.

SOLUTION

The errors in measurement are broadly classified into two categories. systematic error and random error. Parallax error is a kind of personal error which is a source of systematic error. Parallax error occurs when the observer's eye is not at the proper angle with respect to the scale, which makes the object appear to be at a different position on the scale. Random error arises due to unpredictable fluctuation in the measured data and the precision limitations of the measurement device. Due to random error a person could not find the same measurement in exactly the same way.

SOLUTION

Chandrasekhar unit is used for indicating the maximum mass of a white dwarf star which is equivalent to 1.44 solar mass, beyond this limit stars either explode into a supernova or become neutron star or a black hole.

SOLUTION

An atomic clock is a device that measures time by tuning the frequency of microwave wave with the atomic oscillation when they change energy levels. The atomic clocks are so precise and consistent that they would have to run for thousand years before their readings would differ by more than 1 second.

SOLUTION

The magnitude of a physical quantity and units are inversely proportional to each other. Larger the unit, smaller will be the magnitude. The product of numerical value and the unit remains constant.

SOLUTION

Radian is an angular unit and is the plane angle subtended by a circular arc at the centre of the circle as the length of the arc divided by the radius of the arc.

SOLUTION

1 light year = 9.46  10¹⁵ m. 1 parsec =3.086 10¹⁶ m.  1 parsec = [(3.086 10¹⁶ m)/(9.46  10¹⁵ m)] light years

SOLUTION

kilogram is the unit of mass.  

SOLUTION

A. Surface tension = force/length, dimensions - [M¹ L⁰ T^-2] B. surface energy = Potential energy / area, dimensions - [M¹ L⁰ T^-2] C. Pressure = force / area, dimensions - [M¹ L^-1 T^-2] D. Planck's constant = energy / frequency, dimensions - [M¹ L² T^-1]

SOLUTION

Magnetic moment =current X area

SOLUTION

1 giga meter = 10⁹ meter = 1000 x 10⁶ meter = 1000 mega meter (1 mega meter = 10⁶ meter)  

SOLUTION

Power = work/time = [ML²T^-2]/[T]                                = [ML²T^-3]  

SOLUTION

From the tention formula

SOLUTION

x = at + bt² Writing the equation in dimensional form, [L ] = a [T] + b [T²] Applying the principle of homogeneity of dimensions, a must have the dimensions of [LT^-1].

SOLUTION

From E=1/2 mv²

SOLUTION

From the formula E=1/2kx²

SOLUTION

SOLUTION

dyne/cm in C.G.S. unit while S.I. is a M.K.S. unit

SOLUTION

 2x10⁹ s>3x10⁷ s>8.6x10⁴ s>1x10⁰ s

SOLUTION

6.4x10⁶ m>1.8x10⁰ m>1x10^‑4 m>5x10^-11 m

SOLUTION

From velocity of sound in the air =333 m/s
and three second =333.34 x 3= 1000.02= 10³ (approx)

SOLUTION

As 1.66 x 10^-27 kg = 1 a.m.u., 1 kg = 1/ (1.66 x 10^-27) a.m.u. = 0.6 x 10²⁷ a.m.u.

SOLUTION

In M.K.S. system of units, metre, kilogram and second are taken as fundamental units of length, mass and time respectively.

SOLUTION

Power = work/ time Unit of Power - J/s (watt)

SOLUTION

SOLUTION

SOLUTION

As the causes of systematic errors are known, these errors can be minimized. The sources of these errors along with the method of their reduction are given below. 1. Instrumental errors - these can be reduced by using more accurate instruments. 2. Imperfection in experimental techniques - these can be reduced by improving experimental techniques. 3. Personal errors - these can be reduced by removing personal errors. 4. Least count error - these can be reduced by using instruments of higher resolution and by improving experimental techniques.

SOLUTION

Dimensions of (A) Energy - [M L² T^-2] and Latent heat - [L² T^-2] (B) Light year - [L] and Time - [T] (C) Planck's constant - [M L² T^-1] and Wein's constant - [L K] (D) Torque - [M L² T^-2] and Work - [M L² T^-2]

SOLUTION

The no of significant digits in length is 4. so the area should be rounded off to 4 digits Surface area of cube = 6(7.203)²m²                                   = 311.299254m²                                  =311.3m²

SOLUTION

Gravitational force, F = G m₁m₂/r²

SOLUTION

500.0 has 4 significant digits.

SOLUTION

SOLUTION

The SI unit used to specify amount of substance (or quantity of matter) is mole. One mole is the amount of substance which contains as many elementary entities (atoms, molecules, ions, electrons etc.) as there are atoms in 0.012 kg of pure C¹².
 

SOLUTION

SOLUTION

SOLUTION

SOLUTION

 Light year is the distance travelled by light in one year in vacuum.

SOLUTION