Question

Can you please answer that question with clear explanation

Answer 1

Answer:

Given:

A vector representation of velocity has been provided as follows :

v = 3i + 4j + 5k

To find:

Kinetic energy of the body.

Formulas used:

KE = ½mv² ,

where m => mass and v => resultant velocity vector

Concept:

First you need to find out the resultant velocity from the vector representation.

Calculation:

$|v | = \sqrt{ ({3}^{2} + {4}^{2} + {5}^{2}) }$

Since they are mutually perpendicular vectors we can directly write the above equation.

$= > |v| = \sqrt{50}$

$|v| = 5 \sqrt{2} \: m {s}^{ - 1}$

Now Kinetic energy

$= \frac{1}{2} m {( |v| )}^{2}$

$= \frac{1}{2} \times (1.5) \times {(5 \sqrt{2} )}^{2}$

$= \frac{1}{2} \times (1.5) \times 50$

$= \frac{150}{4}$

$= 37.4 \: joules$

So final answer is 37.5 joules.

Answer 2

$\huge{\underline{\underline{\mathfrak\green{ANSWER:-}}}}$

$\large{\underline{\underline{\mathfrak\pink{formula:-}}}}$

K. e=½mv²

$\large{\underline{\underline{\mathfrak\blue{solution\::}}}}$

here,

v=3i +4 j+5k.

.°.|v|=√3²+4²+5²

.°.|v|=√50

.°.|v|=5√2m/s.

ALL VALUES PUT IN FORMULA ,

THEN WE GET,

.°. K. e=½m(|v|)²

.°.k. e=½×1.5×(5√2)²

.°.K. e=½×1.5×50

.°.k. e=150/4

.°.K. E=37.5J

$\huge{\underline{\underline{\mathfrak\purple{THANKS.}}}}$