Question

physic problem A fuel tank explodes, ripping the container into two pieces of masses 11 kg and 15 kg and sending them 12.0 m and 11.0 m high, respectively. What was the energy released by the explosion if all energy becomes the KE of the fragments?

Answer 1

`E = 2910.6 J`

Step-by-step explanation:

As the explosion occurs there is no external force on them

So here we can say that total momentum must be conserved

So we will have

`m_1 v_1 = m_2 v_2`

in vertical direction the two parts will reach to maximum height of 12 m and 11 m respectively

So their speeds are given as

`v_(y1) = √(2gh_1)`

`v_(y1) = √(2(9.81)(12)) = 15.3 m/s`

`v_(y2) = √(2(9.81)(11)) = 14.7 m/s`

now we have

Energy of explosion = kinetic energy of both parts after explosion

So we will have

`E = (1)/(2)m_1v_1^2 + (1)/(2)m_2v_2^2`

`E = (1)/(2)11(15.3)^2 + (1)/(2)15(14.7)^2`

`E = 2910.6 J`