Multiple Choice
A spring with spring constant 800 N/m compressed 0.200 m is released and projects a 0.800 kg mass along a frictionless surface.The mass reaches a surface area where μk = 0.400 and comes to a stop.The following student solution contains at least one error.What is the error? 
A) The elastic potential energy is equal only to the kinetic energy on the right,and is never equal to the internal thermal energy.
B) The elastic potential energy is equal only to the internal thermal energy on the right,and is never equal to the kinetic energy.
C) The elastic potential energy is equal to either the kinetic energy or the internal thermal energy on the right,but not to their sum,depending on the part of the problem being done.
D) Elastic potential energy cannot end up as internal energy change caused by friction.
E) Change in mechanical energy by friction cannot end up as elastic potential energy.
Correct Answer:

Verified
Correct Answer:
Verified
Q25: As a 1.0-kg object moves from point
Q31: A 25-kg block on a horizontal surface
Q47: A 3.50 kg block is pulled along
Q49: Which of the following is a conservative
Q55: As an object moves from point A
Q61: A particle is acted upon by only
Q62: A champion athlete can produce one horsepower
Q65: A 2.0-kg block sliding on a rough
Q67: A 1.2-kg mass is projected from ground
Q84: A 1.0-kg block is released from rest