If you could please give me a already given speed I could estimate it. since there is no speed shown you wouldn't be able to estimate the speed of the moving train.
Answer:
Explanation:
Inital KE = (1/2) m v^2 = (1/2) * 1500 * 50^2 = 1,875,000 J
Final KE = (1/2) * 1500 * 100^2 = 7,500,000 J
But ,
4 * 1875000 = 7500000
so the KE has increased by 4 times.
Answer:
Microlensing.
Explanation:
This techniques is called Microlensing.
Microlensing is a method of gravitational lensing where light from a backdrop point of origin is curved to develop distorted, numerous and/or lightened images by the gravity field of a foreground lens.
This method is very effective in discovering planets that are far-far from earth.It is actually an astronomical effect that was predicted by Albert Einstein's general theory of relativity.
Answer:
C) steel turning to rust in salt air
Explanation:
The missing options are:
A) ice melting to form liquid water
B) water boiling to form steam
C) steel turning to rust in salt air
D) sugar dissolving into hot coffee
In a chemical change the atoms of the reacting compounds are reordered forming new compounds. In a chemical change, new compounds appear, but in a physical change not.
Then, change of states like ice melting and water boiling are not chemical changes.
During steel rust, components of steel, like iron, are oxidized, that is, reacts with oxygen forming oxides.
The dissolution of sugar into hot coffee is a physical change in which sugar molecules get further apart in the coffee, but they don't change.