A 5-Kg Projectile Is Fired Over Level Ground with a Velocity

Multiple Choice

A 5-kg projectile is fired over level ground with a velocity of 200 m/s at an angle of 25 ° above the horizontal. Just before it hits the ground its speed is 150 m/s. Over the entire trip the change in the thermal energy of the projectile and air is:

A) +19,000 J
B) -19,000 J
C) +44,000 J
D) -44,000 J
E) 0