148940 An object of mass $7 \mathrm{~kg}$ initially at rest explodes into two pieces $A$ and $B$. The mass of $A$ is $3 \mathrm{~kg}$. and the mass of $B$ is $4 \mathrm{~kg}$. After explosion, $B$ moves with the velocity of $2 \mathrm{~m} / \mathrm{s}$. The ratio of kinetic energy of $A$ to kinetic energy of $B$ is
148940 An object of mass $7 \mathrm{~kg}$ initially at rest explodes into two pieces $A$ and $B$. The mass of $A$ is $3 \mathrm{~kg}$. and the mass of $B$ is $4 \mathrm{~kg}$. After explosion, $B$ moves with the velocity of $2 \mathrm{~m} / \mathrm{s}$. The ratio of kinetic energy of $A$ to kinetic energy of $B$ is
148940 An object of mass $7 \mathrm{~kg}$ initially at rest explodes into two pieces $A$ and $B$. The mass of $A$ is $3 \mathrm{~kg}$. and the mass of $B$ is $4 \mathrm{~kg}$. After explosion, $B$ moves with the velocity of $2 \mathrm{~m} / \mathrm{s}$. The ratio of kinetic energy of $A$ to kinetic energy of $B$ is
148940 An object of mass $7 \mathrm{~kg}$ initially at rest explodes into two pieces $A$ and $B$. The mass of $A$ is $3 \mathrm{~kg}$. and the mass of $B$ is $4 \mathrm{~kg}$. After explosion, $B$ moves with the velocity of $2 \mathrm{~m} / \mathrm{s}$. The ratio of kinetic energy of $A$ to kinetic energy of $B$ is