Complete Question
A car is moving at 56 miles per hour. The kinetic energy of that car is 5 × 105 J. How much energy does the same car have when it moves at 90 miles per hour? Answer in units of J
Answer:
[tex]K.E_2=640000J[/tex]
Explanation:
From the question we are told that:
Initial Velocity [tex]v_1=56 mil/h=>25.0342m/s[/tex]
[tex]K.E_1=5*10^5J[/tex]
Final Velocity [tex]V_2=90mil/h=>40.2336m/s[/tex]
Generally the equation for Kinetic Energy is mathematically given by
[tex]K.E=0.5mv^2[/tex]
Therefore
[tex]K.E_1=0.5mv_1^2[/tex]
[tex]5*10^5J=m(25.0342)^2[/tex]
[tex]m=797.82kg[/tex]
Therefore The Final K.E_2 is
[tex]K.E_2=0.5mv_2^2[/tex]
[tex]K.E_2=0.5*(797.82kg)(40.2336m/s)^2[/tex]
[tex]K.E_2=640000J[/tex]
