Question

the cross country skier moved a long a level path at a constant speed. does the kinetic energy or potential energy increase, decrease, or stay constant?

Answer 1

The kinetic energy of the skier in terms of mass and speed is,

`K=(1)/(2)mv^2`

The speed and mass of the skier remain constant during the motion.

Thus, the value of the kinetic energy of the skier remains constant.

The potential energy of the skier in terms of mass and height is,

`U=mgh`

where g is the gravitational constant,

As the skier is moving along the level path, thus, the height of the skier remains constant.

The mass of the skier is constant.

Thus, the potential energy of the skier remains constant.