Question 4.1:State, for each of the followi volume, mass, speed, acceler displacement, angular veloci
AnswerScalar:
Volume, mass, spee
Vector:
Acceleration, veloci A scalar quantity is specified associated with it. Volume, are some of the scalar physic A vector quantity is specifie Acceleration, velocity, displa Question 4.2:Pick out the two scalar quant force, angular momentum, w velocity, magnetic moment,
AnswerWork
and
current
are scala Work done is given by the d of two quantities is always a Current is described only by it is a scalar quantity. g physical quantities, if it is a scalar or a vecto ation, density, number of moles, velocity, angul y. , density, number of moles, angular frequency y, displacement, angular velocity by its magnitude only. It does not have any dir ass, speed, density, number of moles, and angu al quantities. by its magnitude as well as the direction assoc cement, and angular velocity belong to this cat ities in the following list: ork, current, linear momentum, electric field, av elative velocity. quantities. t product of force and displacement. Since the scalar, work is a scalar physical quantity. its magnitude. Its direction is not taken into acc : ar frequency, ction lar frequency ated with it. gory. erage ot product unt. Hence,
Question 4.3:Pick out the only vector qua Temperature, pressure, impu potential, coefficient of fricti
Answer
ImpulseImpulse is given by the prod product with time (a scalar q Question 4.4:State with reasons, whether t physical quantities are meaniadding any two scalars, (b) a multiplying any vector by an vectors, (f) adding a compon
AnswerAnswer:
Meaningful Not MeaningfulMeaningfulMeaningful tity in the following list: lse, time, power, total path length, energy, gravi on, charge. ct of force and time. Since force is a vector qu antity) gives a vector quantity. e following algebraic operationswith scalar an ngful: dding a scalar to a vector of the same dimensio scalar, (d) multiplying any two scalars, (e) ad ent of a vector to the same vector. tational ntity, its d vector s, (c) ing any two
MeaningfulMeaningful
Explanation:(a)
The addition of two scala physical quantity.
(b)
The addition of a vector q A scalar can be multiplied w give impulse.A scalar, irrespective of the scalar having the same or dif The addition of two vector q physical quantity.A component of a vector can dimensions.Question 4.5:Read each statement below c The magnitude of a vector is scalar, (c) the total path leng vector of a particle. (d) the a divided by the time taken to average velocity of the partic in a plane can never add up t
AnswerAnswer:
TrueFalse quantities is meaningful only if they both repre uantity with a scalar quantity is not meaningful. th a vector. For example, force is multiplied wi hysical quantity it represents, can be multiplied ferent dimensions. antities is meaningful only if they both represe be added to the same vector as they both have t arefully and state with reasons, if it is true or fa always a scalar, (b) each component of a vecto h is always equal to the magnitude of the displa erage speed of a particle (defined as total path l over the path) is either greater or equal to the le over the same interval of time, (e) Three vect give a null vector. sent the same h time to with another t the same he same se: is always a cement ength agnitude of ors not lying
FalseTrueTrue
Explanation:
The magnitude of a vector is Each component of a vector Total path length is a scalar the total path length is alway equal to the magnitude of dis It is because of the fact that t magnitude of displacement o Three vectors, which do not taken in the same order.Question 4.6:Establish the following vect 
a
+
b

≤ 
a
 + 
b

a
+
b

≥ 
a

− 
b

a
−
b

≤ 
a
 + 
b

a
−
b

≥ 
a

− 
b
When does the equality sign
Answer
Let two vectors and be as shown in the given figure. a number. Hence, it is a scalar. s also a vector. uantity, whereas displacement is a vector quant
s greater than the magnitude of displacement. It placement only when a particle is moving in a s e total path length is always greater than or eq f a particle. ie in a plane, cannot be represented by the sides r inequalities geometrically or otherwise: above apply? epresented by the adjacent sides of a parallelog ity. Hence, becomes traight line. al to the of a triangle am OMNP,