PostsCommentsPayoutsdhingrapranay15 (28)in #knowledge • 7 years agohow an automatic fire alarm worksThe automatic fire alarm system uses the fact that different solids expand by different amounts on heating . The alarm contains two metal stripes , one of iron and the other of…dhingrapranay15 (28)in #life • 7 years agofidget spinnerhi guys , so There’s a new, dumb trend: the fidget spinner. It’s a toy like a top, but spin in the hand rather than on a surface. The user holds a pad at the center, and flicks…