Question

the quantity has a value of -10m/sec. it may be the
(a) displacement of particle
(b) velocity of particle
(c) position of particle
(d) speed of particle​

Answer 1

Required Answer:-

The given quantity is -10 m/s.

The unit is metre/sec which means length is divided by time which results in this quantity. This can be either velocity or speed. Now, we can see them both in the options.

• Velocity is a vector quantity which is expressed by both direction and magnitude. It can positive, negative or zero.

• Speed is a scalar quantity which is expressed by magnitude only. It can be positive only for a moving body$.$

Hence:-

The quantity represented by the value -10 m/s is the velocity of particle i.e. Option B.

Rest options:-

• Displacement has a unit of m. (A/q)
• Position can't be negative (distance travelled is the actual length covered).
• Speed can't be negative.

Answer 2

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$\Large{\bf{\green{\underline{GiVeN\::}}}}$

• A value of a quantity is -10 m/s.

$\\ \Large{\bf{\orange{\underline{To\:Search\::}}}}$

• The presentation of the quantity.

$\\ \Large{\bf{\purple{\underline{\textsf{\textbf{Step-by-step\:Explanation\::}}}}}}$

(a) Displacement of particle ; -

➣ Displacement is the measurement of the length of the shortest path from the initial point to the final point.

➛ Displacement is a vector quantity having direction as well as magnitude.

↝ S.I unit of displacement is 'meter' (m).

$\Large\bf\blue{Therefore,}$

✅ First option is wrong, because the unit of given quantity is 'm/sec', but the unit of displacement of particle is 'm'.

(b) Velocity of particle ; -

➣ Velocity is the displacement covered by a body in a unit time.

➛ Velocity is a vector quantity.

↝ S.I unit of velocity is 'meter/second' (m/sec).

➻ Velocity (average) can be negative as a negative value would mean the object is travelling at the opposite direction than the intended one.

$\Large\bf\green{Therefore,}$

✅ Second option is right, because the unit of given quantity is 'm/sec' and the unit of velocity of particle is 'm/sec' and the value of velocity can be negative, as the given data also represents a negative value.

(C) Position of particle ;-

➣ Position is how a person or thing is placed or opinion or where a person or thing is located in relation to others.

✒ An example of position is sitting.

➛ Position is a vector quantity.

↝ It has no unit.

$\Large\bf\orange{Therefore,}$

✅ Third option is wrong, because Position of particle has no unit.

(d) Speed of particle ;-

➣ Speed is the distance travelled by a body in a unit time.

➛ Speed is a scalar quantity.

↝ S.I unit of speed is 'meter/second' (m/sec).

➻ The ratio of distance travelled and the time taken by a body can be zero but not negative. Since distance and time are positive quantities and speed is obtained by the ratio of these two quantities, hence speed cannot be negative.

$\Large\bf\pink{Therefore,}$

✅ Fourth option is wrong, because the unit of given quantity is 'm/sec' and the unit of speed of particle is also 'm/sec', but the value of speed cannot be negative and it is given that the value the quantity is -10 m/s. That's why it's wrong option.