The decrease in stress is given by
\sigma =\sigma _(0)exp(-(t)/(\tau ))
.
At
20\deg C
, a stress of
9MPa
is applied to an elastomeric material at a constant stress.
After 25 days, the stress decreases to
8MPa
.
What is the relaxation time
\tau
for this material?
T=
days (*Round to the nearest integer.)
What will be the stress after 50 days?
Answer:
,MPa
(*show up to the 2nd decimal place.)
A