Aconstant horizontal pull acts on a sled on a horizontal frictionless ice pond. the sled starts from rest. when the pull acts over a distance x, the sled acquires a speed v and a kinetic energy k. if the same pull instead acts over twice this distance:

If the same pull instead acts over twice this distance,

C) The sled’s speed will be v√2 and its kinetic energy will be 2K.

Newton's second law of motion states that the resultant force applied to an object is directly proportional to the mass and acceleration of the object.

F = Force ( Newton )

m = Object's Mass ( kg )

a = Acceleration ( m )

Let us now tackle the problem !

Complete Question:

A constant horizontal pull acts on a sled on a horizontal frictionless ice pond. The sled starts from rest. When the pull acts over a distance x, the sled acquires a speed v and a kinetic energy K. If the same pull instead acts over twice this distance:

A) The sled’s speed will be 2v and its kinetic energy will be 2K.

B) The sled’s speed will be 2v and its kinetic energy will be K√2.

C) The sled’s speed will be v√2 and its kinetic energy will be 2.

D) The sled's speed will be v√2 and its kinetic energy will be K√2.

E) The sled's speed will be 4v and its kinetic energy will be 2K.

We will use following formula to solve this problem:

Let's compare the two situations by using above formula:

If the same pull instead acts over twice this distance,

C) The sled’s speed will be v√2 and its kinetic energy will be 2K.

Grade: High School

Subject: Physics

Chapter: Dynamics