AP EAMCET Engineering 2018 Apr 22 Shift 2 Paper

The following figure represents the required diagram. Before explosion momentum is given by,
Mbe=mu‌cos‌θ×2
After explosion momentum is given by,
Mae=−mu‌cos‌θ+mv2
Use conservation of momentum.
=mu‌cos‌θ×2=−mu‌cos‌θ+mv2
mv2=3mu‌cos‌θ
v2=3u‌cos‌θ
The kinetic energy of first part is given by,
E1=

1

2

mv12
=

1

2

m(−u‌cos‌θ)2
=

1

2

mu2cos2θ
The kinetic energy of second part is given by,
E2=

1

2

mv22
=

1

2

m(3u‌cos‌θ)2
=

9

2

mu2cos2θ
=9E1