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x Homework 7-Even MORE x C Chegg G arctan formula Google Se... x Connecting A Sm

ID: 1431826 • Letter: X

Question

x Homework 7-Even MORE x C Chegg G arctan formula Google Se... x Connecting A Small Block Of M 2. k 8 Work d E 3 b/Student/Assig dep-13131537 Search 11. 215 points l Previous Answers SerPSE8 8.P041 My Notes Ask Your Teacher A small block of mass m- 115 g is released from rest at point along the horizontal diameter on the inside of a frictionless, hemispherical bowl of radius R 29.5 cm as shown in the figure below 2R/3 (a) Calculate the gravitational potential energy of the block-Earth system when the block is at point A relative to point 3 0.332 (b) calculate the kinetic energy of the block at point 3 0.332 (c) Calculate its speed at point 3 Enter a number, differs from the correct answer by more than 10%. Double check your calculations. m/s d) Calculate its kinetic energy when the block is at point O e) calculate the potential energy when the block is at point O Need Help? Read Talk to a Tutor Submit Answer Save Progress Practice Another Version 12. -13 points SerPSE8 86. P 045. My Notes Ask Your Teacher A skateboarder with his board can be modeled as a particle of mass 80.0 kg, located at his center of mass (which we will study in a later chapter). As shown in the figure below, the 3:30 PM

Explanation / Answer

(c) At point B

KE = PE

(1/2) m vb2 = mgR

vb2 = 2gR

vb2 = 2 x (9.8 m/s2) (0.295 m)

vb = 2.40 m/s

(d) At point C, the vertical distance is h = (2/3)R

By conservation of energy UC = m g hC = (2/3) m g R

Since the bowl is frictionless, we know energy is conserved. This means the energy at point C is the same as the initial energy at point A

EC = KC + UC = EA

KC = EA - UC

KC = m g R - (2/3) m g R

KC = (1/3) m g R

KC = (1/3) (0.115 kg) (9.8 m/s2) (0.295 m)

KC = 0.111 J

(e) Potential energy UC = mg(2/3)R = (2/3) mgR

UC = (2/3) (0.115 kg) (9.8 m/s2) (0.295 m)

UC = 0.222 J