Which of the following are true (choose all that apply)? sound can travel through a vacuum. -sound can travel through water. light can travel through a vacuum sound can travel through air. light can travel through air light can travel through water

option (A) - false

option (B) - true

option (C) - true

option (D) - true

option (E) - true

option (F) - true

Explanation:

The sound waves are mechanical waves that means they need a medium to travel.

The light waves are non mechanical waves it means they do not need a medium to travel.

Sound cannot travel trough vacuum.

Sound can travel through air and water.

Light can travel trough vacuum and in air and in water.

option (B) - true

option (C) - true

option (D) - true

option (E) - true

option (F) - true

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