Question #7009d

1 Answer
Dec 13, 2017

#118.2 " Joules"#

Explanation:

Work done = change in energy

#E_1 = (1/2)*m*v_1^2#

#E_2 = (1/2)*m*v_2^2#

#E_2 - E_1 = (1/2)*m (v_2^2 - v_1^2) #

#m = 19.7" kg"#, #v_1 = 2m//s#, #v2 = 4 m//s#

#E_2 - E_1 = (1/2)*19.7(4^2 - 2^2) #

#E_2 - E_1 = (1/2)*19.7(16 - 4) #

#E_2 - E_1 = (1/2)xx19.7xx12 #

#E_2 - E_1 = 6xx19.7 #

#E_2 - E_1 = 118.2 " Joules"#