How much work is required to stretch an ideal spring of spring ...

[imowrer]

How much work is required to stretch an ideal spring of spring constant (force constant) 40 N/m from x = 0.20 m to x = 0.25 m if the unstretched position is at x = 0.00 m?
 
  A) 0.45 J
  B) 0.80 J
  C) 1.3 J
  D) 0.050 J

Question 2

A puck with a mass m1 = 50 g moving at 1.0 m/s approaches a stationary puck with a mass m2 = 100 g on a frictionless air table, and they undergo a sudden two-dimensional elastic collision.
 
  After the collision, both pucks have identical speeds, but travel in different directions. What is the angle between the original and final paths of puck with mass m1? A) 30
  B) 60
  C) 90
  D) 120
  E) 150

[Jevvish]

Answer to Question 1

A

Answer to Question 2

C