Answer:
Before sled starts to move it has a potential energy due to the elevation...and then that potential energy converted to kinetic energy due to presence of a velocity...the sled will continue to move if their is no resesive force...but however friction force is presence that cause the sled to stop....
Answer:

Explanation:
The torque applied by a force can be calculated as

where
F is the magnitude of the force
d is the length of the arm
is the angle between the direction of the force and the arm
In this problem, we have
F = 15 N
d = 2.0 m

Substituting into the equation, we find

When heat energy is transferred from direct contact between a warm and a cold object , it is known as heat transfer by conduction.
In conduction, the heat transfer takes place within an object or between two objects in contact until the temperature becomes uniform. this kind of heat transfer continues until the temperature at two ends between which the heat transfer take place , becomes equal. Heat transfer takes place from point at high temperature to point at lower temperature.
Explanation:
The formula to determine the eccentricity of an ellipse is the distance between foci divided by the length of the major axis