in which of the following is kinetic friction present?

a. between the tires of a car parked on the road.
b. between the floor and a rolling marble.
c. between a dribbling ball and the floor.
d. between a parachute and air.


which of the following statement best describe speed.

a. speed is always increasing.
b. speed is always constant in every moving object.
c. speed is zero when the object travels the shortest time.
d. speed is the total distance travelled over a period time.

in which of the following is static friction present?

a. between the tires of a car parked on the road.
b. between the floor and a rolling marble.
c. between dribbling ball and the floor.
d. between a parachute and the air. ​