A block of mass 1 kg on a horizontal surface is attached to a horizontal spring of negligible mass and spring constant 100 N/m. The other end of the spring is attached to a wall, and there is negligible friction between the block and the horizontal surface. When the spring is unstretched, the block is located at x=0 m. The block is then pulled to x-0.5 m and released from rest so that the block-spring system oscillates between x=-0.5 m and x=0.5 m, as shown in the figure.
Which of the following descriptions about the system are correct? Select two answers.
Responses
-The kinetic energy of the block and the spring potential energy of the system at x equals 0.25 meter are both half of the total mechanical energy of the system.
-The spring potential energy of the system at x equals 0.25 meter is nearly 3.13 joules .
-The kinetic energy of the system at x equals 0.3 meter is nearly 4.5 joules .
-The sum of the spring potential energy of the system and the kinetic energy of the block at x-0.4 m
is nearly 12.5 J.