Solution Found!
For the cases shown in Fig. Q6.8, the object is released
Chapter 3, Problem 8DQ(choose chapter or problem)
For the cases shown in ?Fig. Q6.8?, the object is released from rest at the top and feels no friction or air resistance. In which (if any) cases will the mass have (i) the greatest speed at the bottom and (ii) the most work done on it by the time it reaches the bottom?
Questions & Answers
QUESTION:
For the cases shown in ?Fig. Q6.8?, the object is released from rest at the top and feels no friction or air resistance. In which (if any) cases will the mass have (i) the greatest speed at the bottom and (ii) the most work done on it by the time it reaches the bottom?
ANSWER:Step 1 of 2
(a).Consider the energy conservation principle to calculate greatest speed of the ball at bottom
\(U_{i}+K_{i}=U_{f}+K_{f}\)
Here \(U\) and \(K\) are the potential and kinetic energy of the ball at the initial and final stage.
Where \(U g h\) and \(_{i}=m K_{i}=0\)
\(U\) and \(_{f}=0 \mathrm{~K} / 2 \mathrm{mv}_{f}=1^{2}\)
\(m g h=1 / 2 m v^{2}\)
\(v=\sqrt{2 g h}\)
Here \(\mathrm{m}\) is mass of the ball, \(g\) is gravity and \(h\) is height.
Hence,the bottom speed of the ball in all cases is the same as \(\sqrt{2 g h}\).