Question

a body of mass 1 kg is moving with velocity of 3i +4j m/s the kinetic energy possessed by it will be ......​

Answer 1

ANSWER

K.E=0.5m×v

2

Given m=1kg;v=10 m/s.

K.E=0.5×1×100=50J

Hence kinetic energy is 50 Joule.

Answer 2

Answer:

A body with a mass 1 kg and the velocity is 3i +4j m/s then the kinetic energy possessed by it will be 12.4J

Explanation:

• The kinetic energy of a particle with mass (m) with velocity (v) is equal to

        $KE=\frac{1}{2}mv^{2}$

• The  magnitude of a vector in its component form, that is

        vector $A=ai+bj+ck$ ,

         magnitude is $/A/=\sqrt{a^{2} +b^{2} +c^{2} }$

From the question, we have

mass of the body $m=1kg$

velocity in vector form $v=3i+4j m/s$

the magnitude of the velocity $/v/=\sqrt{3^{2} +4^{2} }$

⇒$/v/=\sqrt{25} =5m/s$

now the kinetic energy of the body

$KE=\frac{1}{2} *1*5^{2}$

⇒$KE=12.4J$