Final answer:
The change in velocity of a body moving at 20 m/s and changing direction by 120 degrees while maintaining the same speed is 20 m/s.
Step-by-step explanation:
Change in Velocity
The question requires calculating the change in velocity of a body moving initially at 20 meters per second at an angle of 60 degrees, and then continuing with a velocity of 20 meters per second. To determine the change in velocity, we need to consider the initial and final velocity vectors. Since the magnitude of the velocity remains the same, and the direction changes by 120 degrees (from 60 degrees to -60 degrees with respect to the positive x-axis), we can use vector subtraction or geometry to find the resultant change in velocity.
In this case, assuming the angles are measured from the positive x-axis and the motion is within a plane, the body changes direction by 120 degrees while maintaining the same speed. By constructing a vector diagram or using trigonometry, it is possible to show that the magnitude of the change in velocity is equal to twice the magnitude of the original velocity times the cosine of half the angle between the vectors, leading to a change in velocity of 20 meters per second.