CPU temperature reaches 100 degree on stress when plugged in

My laptop runs fine when using battery and plugged in while normal use. But whenever I try to load some heavy software like android studio or install a game or run a game. The temperature shoots up to 100 degree. When i unplug the charger it goes back to normal like 70 degree and goes up only when it is plugged in. The adapter is original one and tried using another one too but got no change. One thing more the fan runs alot faster that time and when i touch my laptop it isn't as hot as it should be for 100 degrees but pretty normal. Should I be worried or just get on with it.

Question by abd on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.