Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review problem 0 a.Draw an energy graph for this situation. Assume U = 0 at x = 0. b.At x = 0, the object has 2 J of kinetic energy. What is the maximum KE of the object?

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review problem 0 a.Draw an energy graph for this situation. Assume U = 0 at x = 0. b.At x = 0, the object has 2 J of kinetic energy. What is the maximum KE of the object? 8 Joules.

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #1 The water skier is going to ski up the ramp, and sail over a 5.0-m-wide tank filled with hungry sharks. The horizontal top of the ramp is frictionless, but the 30° incline is not, with u k = How fast must she be going at the bottom of the ramp to repeat this stunt? θ

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #1- answers The water skier is going to ski up the ramp, and sail over a 5.0-m-wide tank filled with hungry sharks. The horizontal top of the ramp is frictionless, but the 30° incline is not, with u k = How fast must she be going at the bottom of the ramp to repeat this stunt? v top = m/s v bot = m/s θ

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Question #2 A 1 kg object has the potential energy shown in the graph a.The object starts at rest at x = 0 m. What is its speed at x = 3 m? b. Does the object have a turning point? If so, where is it? c. Draw a force graph for this situation.

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Question #2 - answers A 1 kg object has the potential energy shown in the graph a.The object starts at rest at x = 0 m. What is its speed at x = 3 m? 1.4m/s b.Does the object have a turning point? If so, where is it? Yes, at x = 4m. c.Draw a force graph for this situation

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Question #3 (EXAMPLE 12.17) A 3.0 m long ladder leans against a frictionless wall at an angle of 60°. What is the minimum value of μ s the coefficient of static friction with the ground, so that the ladder does not slip?

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.

EXAMPLE Will the ladder slip?

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #4 A 40 g ball is dropped from rest from a height of 1.8 m, and rebounds to a height of 1.2 m. The figure shows the impulse received from the floor. a. Compare the force due to gravity with the force due to the floor during the impact. b. For how much time was the ball in contact with the floor? Use the impulse approximation.

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #4 - Answer A 40 g ball is dropped from rest from a height of 1.8 m, and rebounds to a height of 1.2 m. The figure shows the impluse received from the floor. a. Compare the force due to gravity with the force due to the floor during the impact. F G = -.392N and is constant b. For how much time was the ball in contact with the floor. Use the impulse approximation. t = 24 ms

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #5 Find an expression for F, the magnitude of the horizontal force for which m 1 does not slide up or down the wedge. This expression should be in terms of m 1, m 2, θ, and any known constants, such as g. All surfaces are frictionless. Draw the FBDs for m 1 and m 2. Connect the Newton’s Third law pairs with a dotted line

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #5 Slippage=0 when both blocks have equal acceleration in the horizontal direction and 0 acceleration in the vertical direction. Therefore, both FBDs should be true horizontal/vertical.

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #5. F = (m 1 + m 2 ) g tan θ

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review #6 – (Ch 8, 48) A 60-gram ball is tied to the end of a 50-cm long string and swung in a vertical circle. The center of the circle, as shown in the figure, is 150 cm above the ground. The ball is swung at the minimum speed necessary to make it over the top without the string going slack. If the string is cut at the instant the ball is at the top of the loop, how far to the right does the ball hit the ground?

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review #6 – (Ch 8, 48)- Answer v = 2.21 m/s horizontally the time for the projectile to hit the ground is: t =.64 s x = 1.41 m from the point of release

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review problem #7 The diagram shows a uniform, A-shaped stepladder of 20.0 kg, on a horizontal frictionless surface. The only thing that keeps the ladder from collapsing is the crossbar (negligible mass). Determine the tension in the crossbar.

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review problem #7 - answer The diagram shows a uniform, A-shaped stepladder of 20.0 kg, on a horizontal frictionless surface. The only thing that keeps the ladder from collapsing is the crossbar (negligible mass). Determine the tension in the crossbar. T = 17.5 N

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem #8

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem 9 A uniform square with sides of 5 cm is rotating about its center of mass at 100 rpm. What is the speed of one of it’s sides?

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem 9 I don’t know. Let’s figure it out.

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem 10 A 100 g granite cube slides down a 40° frictionless ramp. At the bottom of the ramp, it has a perfectly elastic collision with a 200 g steel cube. How high above the table should granite cube be released from rest to give the steel cube a speed of 1.5 m/s?

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Review Problem 10 (ch 10, 43) A 100 g granite cube slides down a 40° frictionless ramp. At the bottom of the ramp, it has a perfectly elastic collision with a 200 g steel cube and stops. How high above the table should granite cube be released from rest to give the steel cube a speed of 1.5 m/s?.26 m