As a demonstration, a physics teacher attaches a 7.5kg object to the ceiling by a nearly massless string. This object then supports a 2.5kg object below it by another piece of string. Finally, another piece of string hangs off the bottom of the lower object to be pulled with ever increasing force until the string breaks somewhere. The string will break when the tension reaches 156 N.
a. Which length of the string will break first?
b. What is the maximum downward force the physics teacher can apply before the string breaks.
PLEASEE EXPLAINN!!!
a. Which length of the string will break first?
b. What is the maximum downward force the physics teacher can apply before the string breaks.
PLEASEE EXPLAINN!!!
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The top string will break first as it takes the bulk of the load.
The initial tension is T=(m1+m2)*g = (7.5+2.5)*9.8 = 98N
Since the string breaks at 156N, the additional load it can take is 156-98=58N
The initial tension is T=(m1+m2)*g = (7.5+2.5)*9.8 = 98N
Since the string breaks at 156N, the additional load it can take is 156-98=58N
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a) the top piece.
the tension on the bottom piece is x
at the next piece, the tension is x+2.5*9.8
at the next piece, the tension is x+2.5*9.8+7.5*9.8 = x+98
obviously the tension is highest in the top piece.
to break, x+98 = 156
x = 58 N
the tension on the bottom piece is x
at the next piece, the tension is x+2.5*9.8
at the next piece, the tension is x+2.5*9.8+7.5*9.8 = x+98
obviously the tension is highest in the top piece.
to break, x+98 = 156
x = 58 N