What is the kinetic energy of an object with a mass of #3 kg# that has been in freefall for #7 s#?

1 Answer
May 19, 2016

Answer:

#E_k=7073.35" "J#

Explanation:

#"first; let's find velocity of object for t=7"#

#v=-g*t#
#v=-9*81*7#
#v=-68.67 m/s#

#"The Kinetic Energy of an object is calculated by:" E_k=1/2*m*v^2#

#m=3 kg#

#E_k=1/2*3*(-68.67)^2#

#E_k=7073.35" "J#