Physics - Center of Mass Question with Solution | TestHub

Restitution keeps the tangential component and multiplies the normal component by e, so$\tan ($ after$)=\tan ($ before$)/e$ (angles measured from the wall normal). At BC (normal horizontal): before,$\tan =\frac{u\cos \theta }{u\sin \theta }=\cot \theta$; after with$e=\frac{1}{2}:\tan {\theta }_1=\frac{\cot \theta }{1/2}=2\cot \theta -$ (C) true. At CD (normal vertical): before,$\tan =\frac{u\sin \theta /2}{u\cos \theta }=\frac{\tan \theta }{2}$; after with$e=\frac{1}{4}:\tan {\theta }_2=\frac{\tan \theta /2}{1/4}=2\tan \theta -$ (B) true. Also$4\cot {\theta }_1=\frac{4\tan \theta }{2}=2\tan \theta =\tan {\theta }_2$ - (D) true. Answer: (B), (C), (D)