The original length of a certain spring is 16 cm. The amount of work required to stretch it to a length of 20 cm is 0.05 J. What is the spring constant? Answer: (5 marks) deltaX = .20m - .16m = .4m k = 2U/(deltaX]^2 K = (2)(0.05)/(0.4)^2 K = 0.625 N/m When the spring described in Problem 4 is stretched to a length of 22 cm, what force is exerted by the spring? Answer: (3 marks)A trunk weighing ED N is pushed up an inclined plane whose angle is 3i)\". \"me amount of work required to move the trunk a distanoe of 3 n1 along the inclined plane is 40]. What is the efficiency.r of this inclined plane? Answer: {5 marks]