3.2. Result by the image analysis
Table 1 shows the incident velocity, incident angle, reflection velocity, reflection angle, and angular
velocity of the ball, as well as the velocity and angle of the racket after the collision, that were
determined from analysis of the images obtained with the high speed camera. These results are applied to
equations (1)-(3) which yield the calculated impulses S1, S2 and S2’ from the change of the momentum.
The reduced mass used for this racket, 0.05[kg] was assumed to be one fourth of the total racket mass.
The radius of the ball r was taken to be 0.0325[m] with the assumption that it did not deform.
3.3. Comparison of Impulses
Fig. 4 shows the vertical component of impulse on the string plane obtained by the two methods using
racket B. The impulse S1 obtained from analyzing images is denoted with (Ⴠ), while that obtained from
measurements of string tension, S1f is denoted with (Ⴄ). The horizontal axis shows incident angle and the