D. the last choice because the info above tells u so
Answer:
Magnitude of kinetic force is the product of the normal force and the coefficient of kinetic friction.
Explanation:
The kinetic frictional force is the force which is experienced in the moving surfaces of bodies.The magnitude of the force is affected by the coefficient of kinetic friction between the material of two bodies in contact. Mathematically, it is expressed as;
Fk=μk*η
where;
- Fk=force of kinetic friction
- μk=coefficient of kinetic friction
- η=normal force
Ball is projected upwards with speed 20 m/s
now using kinematics
here when ball returns back to same position.
total displacement of ball will be zero.
So ball will return to initial position with same speed in opposite direction.
