A simple pendulum has a length of  0.75m and a bob with a mass of  0.15 kg. The bob is released from an angle of 25° relative to a vertical reference line. (a) Show that the vertical height of the bob when it is released is h = L (1 — cos 25°). (b) What is the kinetic energy of the bob when the string is at an angle of 9.0°? (c) What is the speed of the bob at the bottom of the swing? (Neglect friction and the mass of the string.)

Can you please explain how energy conservation with dissipative forces and how work-energy vs energy conservation affects this problem? Thank you!

A mass of 25kg is attached to a spring (k=650N/m) and is hung from a ceiling. The mass is released at a height h when the spring is unstretched. a) What is the speed of the mass when it has fallen a distance of 0.30m?  b) What is the minimum release height (h) if the mass does not strike the floor? Both parts answered.

The force required to compress a non-standard spring as a function of displacement is given by the equationF(x) = -Asin(bx) + kx,where A = 11 N, b = 11 rad/m, and k = 78 N/m. Part (b)  Calculate the work done in joules as the spring is compressed from x = 0 to x1 = 32 cm.  Part (c)  Calculate the work done in joules as the spring is compressed from x1 = 32 cm to x2 = 69 cm

A 4.8 kg box has an acceleration of 1.8 m/s? when it is pulled by a horizontal force across a surface with 4, = 0.50. Find the work done over a distance of 22 cm by the following forces. (Enter your answers in joules.) (a) the horizontal force (b) the frictional force (c) the net work (d) what is the change in kinetic energy of the box?

A block of mass 2 kg is initially at rest on a frictionless surface. A force of 10 N is applied to the block for a distance of 5 meters along the horizontal direction. Calculate the work done on the block and the final kinetic energy of the block. (Note: In this question, assume the force is constant and applied parallel to the displacement of the block.) Take acceleration due to gravity as 9.8 m/s².

Suppose that 60 J of work is done to stretch a bow a distance of 0.5 m.  (a)  What is the increase in potential energy of the bow?  (b)  If the spring constant of the bow is 1200 Nt/m, what distance was the bow stretched?

= 500 N/m) whose other end is fixed. The ladle has a kinetic energy of 4.2 J as it passes A 0.18 kg ladle sliding on a horizontal frictionless surface is attached to one end of a horizontal spring (k through its equilibrium position (the point at which the spring force is zero). (a) At what rate is the spring doing work on the ladle as the ladle passes through its equilibrium position? (b) At what rate is the spring doing work on the ladle when the spring is compressed 0.070 m and the ladle is moving away from the equilibrium position? (a) Number Units (b) Number Units

A 0.40-kg mass attached to a spring is pulled back horizontally across a table so that the potential energy of the system is increased from zero to 155 J. Ignoring friction, what is the kinetic energy of the system after the mass is released and has moved to a point where the potential energy has decreased to 70 J?