Which of following statements about energy are correct select? Select all that apply. A . Energy can be created or destroyed B . Energy is the ability to do work C . Energy is a material substance D . Energy can change from one form to another E . An object can only have one from of energy at a time .

B and C

Explanation:

Energy is simply defined as the capacity to do work and according to the law of conservation of energy (first law of thermodynamics), energy can neither be created nor destroyed but can, however, be converted from one form to another.

An object can have more than one form of energy at a time. For example, a moving object possesses kinetic energy and can also possess heat energy due to the heat generated while overcoming frictional force.

Option A negates the law of conservation of energy while option D is grossly incorrect.

The correct options are B and C.

are their multiple choices ?

explanation:

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