Assuming the incline to be frictionless and the zero of gravitational potential energy to be at the elevation of the horizontal line,
A) the kinetic energy of the block just before it collides with the spring will be equal to mgh.
B) the kinetic energy of the block when it has fully compressed the spring will be equal to mgh.
C) the potential energy of the block when it has fully compressed the spring will be zero.
D) the energy stored in the spring plus the gravitational potential energy of the block when it has fully compressed the spring will be equal to mgh.
E) the potential energy of the block when it has fully compressed the spring will be

Question

Assuming the incline to be frictionless and the zero of gravitational potential energy to be at the elevation of the horizontal line,
A) the kinetic energy of the block just before it collides with the spring will be equal to mgh. 
B) the kinetic energy of the block when it has fully compressed the spring will be equal to mgh. 
C) the potential energy of the block when it has fully compressed the spring will be zero. 
D) the energy stored in the spring plus the gravitational potential energy of the block when it has fully compressed the spring will be equal to mgh. 
E) the potential energy of the block when it has fully compressed the spring will be

Quizplus · Accepted Answer

At the beginning, the block only has gravitational potential energy mgh, and no kinetic energy. As the block moves down the incline, it gains kinetic energy which is converted to potential energy when it compresses the spring. When the spring is fully compressed, all of the block's initial gravitational potential energy has been converted to potential energy stored in the spring.
Therefore, the energy stored in the spring plus the gravitational potential energy of the block when it has fully compressed the spring will be equal to mgh.

Assuming the Incline to Be Frictionless and the Zero of Gravitational