What is the potential energy of a rock that weighs 10.0 kg and is sitting on top of a hill 100 meters high?l

9800 J

Explanation:

P.E = mgh

P.E = (10.0)(9.8)(100) = 9800 J

explanation:

v=uf/(u-f)

= 5.-10/(5+10) convex lens has negative focal length

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