Module 1

Question 1

It is a branch of Physical Science which describes and predicts the conditions of rest or motion of bodies under the action of forces.

Answer 1

Mechanics

Question 2

Three Division of Mechanics

Answer 2

1. Mechanics of Rigid Bodies
2. Mechanics of Deformable Bodies
3. Mechanics of Fluids

Question 3

Two Divisions of Mechanics of Rigid Bodies

Answer 3

1. Statics
2. Dynamics

Question 4

It deals with bodies at rest.

Answer 4

Statics

Question 5

It deals with bodies in motion.

Answer 5

Dynamics

Question 6

Six fundamental principles of Mechanics based on experiments evidences:

Answer 6

1. The Parallelogram Law for the Addition of Forces
2. The Principle of Transmissibility
3. Newton’s Three Fundamental Laws
4. Law of Inertia
5. Law of Acceleration
6. Law of Action and Reaction
7. Newton’s Law of Gravitation

Question 7

This states that two forces acting on a particle maybe replaced by a single force, called the resultant, obtained by drawing the diagonal of the parallelogram which has sides equal to the given forces.

Answer 7

The Parallelogram Law for the Addition of Forces

Question 8

This states that the conditions of equilibrium or of motion of a rigid body will remain unchanged if a force acting at a given point of the rigid body is replaced by a force of the same magnitude and same direction, but acting at a different point, provided that the two forces have the same line of action.

Answer 8

The Principle of Transmissibility

Question 9

If the resultant forces acting on a particle are zero, the particle will remain at rest (if originally at rest) or will move with constant speed in a straight line (if originally in motion).

Answer 9

Newton’s Law of Inertia

Question 10

If the resultant force acting on a particle is not zero, the particle will have acceleration proportional to the magnitude of the resultant and in the direction of this resultant force. F = ma.

Answer 10

Newton’s Law of Acceleration

Question 11

The forces of action and reaction between bodies in contact have the same magnitude, same line of action and opposite sense.

Answer 11

Newton’s Law of Action and Reaction

Question 12

This states that two particles of mass M and m are mutually attracted with equal and opposite forces F and F’ of magnitude F.

Answer 12

Newton’s Law of Gravitation

Question 13

Formula of Newton’s Law of Gravitation.

Answer 13

F = GMm/r^2

Question 14

What is the system of units used?`

Answer 14

International System of Units

Question 15

By international agreement, the
standard meter had been defined as the _________________________-.

Answer 15

distance between two fine lines on a bar of platinum - iridium alloy

Question 16

The 1960 conference redefined the meter as ________________.

Answer 16

1, 650, 763. 73 wavelengths of the reddish - orange light emitted by the isotope krypton - 86.

Question 17

The meter was again redefined in 1983 as the ______________________________

Answer 17

length of the path traveled by light in vacuum during a time interval of 1 / 299, 792, 458 of a second.

Question 18

When the metric system was created, the kilogram was defined _____________________.

Answer 18

as the mass of 1 cubic decimeter of pure water at the temperature of its maximum density (4.0 ̊C / 39.2 ̊F).

Question 19

A ______________- was carefully made to match this quantity of water under the specified conditions.

Answer 19

solid cylinder of platinum

Question 20

Later it was discovered that a quantity of water as pure or as stable as required could not be provided. Therefore the primary standard of mass became the ____________.

Answer 20

platinum cylinder

Question 21

When was the platinum cylinder replaced by a platinum-iridium cylinder of similar mass?

Answer 21

1889

Question 22

Platinum cylinder was replaced in 1889 by?

Answer 22

platinum-iridium cylinder

Question 23

The ___________ redefined the meter as 1, 650, 763. 73 wavelengths of the reddish - orange light emitted by the isotope krypton - 86.

Answer 23

1960 conference

Question 24

The meter was again redefined in _____ as the length of the path traveled by light in vacuum during a time interval of 1 / 299, 792, 458 of a second.  Mass

Answer 24

1983

Question 25

For centuries, time has been universally measured in terms of the _____________.

Answer 25

rotation of the earth.

Question 26

The second, the basic unit of time, was defined as _________________.

Answer 26

1. 1 / 86, 400 of a mean solar day (see Day) or
2. one complete rotation of the earth on its axis.

Question 27

The second was redefined in 1967 in terms of the ________________ - that is, the frequency at which this atom absorbs energy, or 9, 192, 631, 770 hertz (cycles per second)

Answer 27

resonant frequency of the cesium atom

Question 28

What is the resonant frequency of the cesium atom?

Answer 28

frequency at which this atom absorbs energy, or 9, 192, 631, 770 hertz (cycles per second).