Answer:0.29
Explanation:
Given
Car 1 has 7 times the mass of car 2
but 0.6 times the kinetic energy of car 2
suppose car 2 has the mass m and [tex]v_2[/tex] be the velocity
then car 1 has a mass of 7 m
Kinetic Energy of car 1
[tex]K_1=0.5\times 7m\times v_1^2-------1[/tex]
Kinetic energy of car 2
[tex]K_2=0.5\times m\times v_2^2------2[/tex]
divide 1 and 2 we get
[tex]\frac{K_1}{K_2}=\frac{7v_1^2}{v_2^2}[/tex]
[tex]\frac{v_1}{v_2}=\sqrt{\frac{0.6}{7}}[/tex]
[tex]\frac{v_1}{v_2}=0.29[/tex]