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A point moves linearly with deceleration which is given by `dv//dt=-alphasqrt(v)`, where alpha is a positive constant. At the start `v=v_(0)`. The distance traveled by particle before it stops will be |
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Answer» `(dv)/(dt)=-alphav^(1//2)` `int_(v_(0))^(v)v^(-1//2) dv=-alphaint_(0)^(t) dt` `(|v^(-1/2+1)|_(v_(0))^(v))/((-1/2+1))=-alpha|t|_(0)^(t)` `|v^(1/2)|_(v_(0))^(v)=alpha/2t` `sqrt(v)-sqrt(v_(0))=-alpha/2timpliesv=[sqrt(v_(0))-(alphat)/2]^(2)` The particle will stop when `v=0` `t=(2sqrt(v_(0)))/alpha` To calculate the displacement by velocity is lengthy. `(dv)/(dt)=v(dv)/(ds)=-alpha v^(1//2)` `int_(v_(0))^(v) v^(1//2) dv=-alphaint_(0)^(s) ds` `| v^(3//2)|_(v_(0))^(v)/(3/2)=-alphas` `v^(3//2)-v_(0)^(3//2)=-3/2alphas` When particle stops, `v=0` `impliess=(2v_(0)^(3//2))/(3alpha)` |
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