Answer
a). Initial velocity =u=$(16.4x-11.5y) m/s$
Final velocity =v=$(9.06x+4.28y) m/s$
b). Change in velocity =$(-7.34x+15.78y) m/s$
c). Magnitude =$17.33m/s$
The angle = $64.49^{\circ}$ above (-) x axis.
Work Step by Step
a). Initial velocity =u=$20cos35^{\circ}x-20sin35^{\circ}y=(16.4x-11.5y) m/s$
Final velocity =v=$10cos25^{\circ}x+10sin25^{\circ}=(9.06x+4.28y) m/s$
b). Change in velocity =$(9.06x+4.28y)-(16.4x-11.5y)=(-7.34x+15.78y) m/s$
c). Magnitude =$\sqrt ((-7.34)^{2}+15.78^{2})=17.33m/s$
The angle =$tan^{-1}(\frac{15.78}{-7.34})=-64.49^{\circ}$