The basic meaning is the same - for something to go up to a higher level.
The difference is that raise must have a direct object (one thing is making another thing go up) whereas rise does not have a direct object (one thing is going up by itself). Here are some examples:
Something raises something else:
The student raised his hand. o The government will raise taxes. o The store is raising their prices.
Something rises:
In the morning, the sun rises.
She rose from her chair.
(She stood up)
Unemployment has risen by 10%
ne reason for the confusion is that an increase in salary is called a pay raise in American English, but a pay rise in British English.
Arise is similar to rise, but is more formal and abstract. It can also be used to mean "appear":
Several important questions arose during the meeting.
I'd like to work in Japan, if the opportunity arises.
A new spirit of hope has arisen among the country's people.
Sorry, I'll need to cancel our appointment. A few problems have arisen.
Fact
Dr. S.chandrasekhar An indian-born american, who won nobel prize for physics in 1983. According to his theory, the old stars just collapse and disappear in the light of denser stars of low light popularly called chandrasekhar limit. .. More >>