Which of the following are true statements about friction? check all that apply. a. the amount of friction depends on the type of surface and the force of contact. b. friction is a force that acts between two surfaces that are in contact. c. frictional forces cannot cause acceleration of an object. d. the direction of the frictional force varies such that it always opposes motion.

the closer the planet is to the sun, the larger the gravity

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s