A toy car is launched by compressing a horizontal spring by 0.05 m and then releasing it as shown in the figure below. The mass of the toy car is 0.23 kg. The speed of the car after it is launched down the horizontal track is 2.4 m/s. What is the spring constant? You can assume that the track is frictionless and that the toy car starts from rest. Give you answer in N/m and report your answer to 1 decimal place.

3. Please provide full body diagram with explanation

7. The spring is compressed by the mass (m= 2 kg) to half of its original length and then released. The surface is not smooth and has coefficient of friction 0.2. What will be its speed after 2 s. The spring constant is 200 N/m and the unstretched length of the spring is 60 cm.The mass is not connected to the spring and it can slide on the surface after it is released after compression. k m x = 0

A spring with spring constant k has an unstretched length L . A block of mass m is pushed against the spring to compress it to the unknown position x = A. The block is not attached to the spring and the ground is frictionless. Another force acts on the block, attracting it to the point x = 0, with a magnitude c /x2, where c is a known constant. The block is released from rest. Obtain an algebraic equation for the compressed position x = A, such that the block escapes from the attractive force. (To escape means it will go all the way to infinity where it will have zero velocity.)