How do I solve this?

Question

A 0.200-kg particle has a speed of 1.90 m/s at point  and kinetic energy of 7.40 J at point .

(a) What is its kinetic energy at ?

 ______ J

(b) What is its speed at ?

 ______m/s

(c) What is the net work done on the particle by external forces as it moves from  to ?

 ______ J

Answer 1

The kinetic energy at point A is 1/2mV^2 or 0.361 J. As the kinetic energy is 7.40J at point B, the speed is calculated also by using 7.40 = 1/2mV^2 and solving for V = 8.60 m/s. The net work from A to B would be the difference in KE or 7.40J - 0.361J = 7.04J.