1. A wooden duck toy consists of a small wooden duck mounted on four wheels (combined mass M = 1.3 kg, with a length L = 1 m string at the front to pull the toy. A child pulls the wooden duck across flat ground, starting from rest, with a force F_a = 15 N along the string so the string makes an angle q = 40^o from the horizontal.
   1. Draw a diagram of the problem, including a coordinate system and known variables.
   2. Explain how energy conservation does or does not apply to this situation, using at least three sentences.
   3. Determine the work done by the child pulling the toy a distance d = 5 m across the ground.
   4. Find the speed of the toy after traveling d = 5 m across the ground.
   5. Calculate the acceleration of the toy during its motion.
2. A block with mass M = 20 kg and initial speed v₀ = 5 m/s starts on flat ground, then travels down a slope with height h = 40 m and angle q = 10^o. At the bottom of the slope on flat ground is a spring with constant k = 500 N/m.
   1. Draw a diagram of the problem, including a coordinate system and known variables.
   2. Explain how momentum conservation does or does not apply to this situation, using at least three sentences.
   3. Determine the total energy of the block at the top before it begins traveling down the slope.
   4. Find the speed of the block at the bottom of the slope before reaching the spring.
   5. Calculate the maximum compression of the spring by the block.