¡Hellow!
For this problem, first, lets convert the seconds in hours:
5,4x10³
5400
h = sec / 3600
h = 5400 s / 3600
h = 1,5
Let's recabe information:
d (Distance) = 386 km
t (Time) = 1,5 h
v (Velocity) = ?
For calculate velocity, let's applicate formula:

Reeplace according we information:
386 km = v * 1,5 h
v = 386 km / 1,5 h
v = 257,33 km/h
The velocity of the train is of <u>257,33 kilometers for hour.</u>
<u></u>
Extra:
For convert km/h to m/s, we divide the velocity of km/h for 3,6:
m/s = km/h / 3,6
Let's reeplace:
m/s = 257,33 km/h / 3,6
m/s = 71,48
¿Good Luck?
Answer:
The option is B is not true for Hubble telescope.
<h2>
Answer:Radiation-3,Conduction-1,Convection-2</h2>
Explanation:
Radiation is the transfer of heat through electromagnetic waves.
These waves do not require any medium.This is the way we get heat from sun.Radiation is the quickest mode to transfer of heat.
Conduction is the transfer of heat through collisions of atomic particles.
This phenomenon largely occurs in solids like metals.The neighbour atoms sets the atoms into random motion thereby raising the temperature.
Convection is the transfer of heat through actual movement of medium particle.
This phenomenon occurs in gases an liquids.The medium particles actually traverse through the space transferring the heat.
Because chemical changes result in different substances, they often cannot be undone. Some chemical changes can be reversed, but only by other chemical changes.
i think it depends on the speed rate