Describe the relative amounts of potential and kinetic energy for a book in the following situations. a. The book on a high shelf which is 2 meters off the ground.
All energy is in form of potential energy.

b. The book after it has fallen off the 2-meter shelf and is now 1 meter off the ground.
Half of the energy is potential, half is kinetic.

c. The book just before it hits the ground.
All the energy is kinetic.

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