If the theoretical tensile strength of flawless Borosilicate Glass is 5.6 GPa, what is the maximum allowable length of an internal elliptical flaw, whose radius of curvature at the flaw tip is 5 micrometers, if the part must withstand a tensile stress of 250 MPa

Ok i am attempting to my niece attach a galvanized wire (like a tether for a dog) at the corner of two fences, making a tightwire if you will and we drilled a hole in a softball and she hits it. the ? and problem is that we can not get the wire taunt enough where it doesnt sag after hitting the ball once, and the wire sags and wobbbles. its a 15 ft rubber covered galvanized wire and one can adjust the length of the placing of the wire by having it make the corner of 2 fences become a it can be adjusted, however, with all our human strength and pliers we could not make it taunt as possible. is there anything other that attaching it to a car to do this. sorry abt the length but it would mean the world to my niece if i could solve this came up with the entire idea herself, and she is 14 and paid for the wire and did as much work as i did drilling a hole through a softball wide enough for attaching piece at each end of the wire that clips on to the fence. . any ideas welcome if serious. but awesome if it is a fact. much obliged. bucky bukowski buckman

How would doubling the made of an object change the objects potential energy

Pls pls pls pls ! describe, in your own words, how you found the epicenter of the earthquake.