Q. 14

Question


Find 

(a) the displacement vectors from r(a) tor(b), 

(b) the magnitude of the displacement vector, and

 (c) the distance travelled by a particle on the curve from a to b.

 r(t) = t, t2 a = 2, b = 3


Step-by-Step Solution

Verified
Answer

(a) The displacement vector from r(a) to r(b) is 1,5.(b) Magnitude of displacement vector is 26.(c) Thus the distance travelled by the particle from a to b is 3372-17+14ln6+374+17.



1Part (a) Step 1. Given Information

The given function is  r(t) = t, t2 a = 2, b = 3.

2Part(a) Step 2. Finding the displacement vector

 r(t) = t, t2 a = 2, b = 3.

=r(b) -ra(a) The displacement vector from r(a) to r(b) =r(b) -ra(a)                                                                            =r(3)-r(2)                                                                            =3,32-2,22=3,9-2,4=3,-2,9-4=1,5The displacement vector from r(a) to r(b) is 1,5


3Part (b) Step 1. Magnitude of displacement vector

Magnitude of displacement vector =1,5

=12+52=26

Magnitude of displacement vector is 26.

4Part (c) Step 1. The distance travelled by a particle on the curve from a to b.

r(t) =t,t2r'(t) =1,2tr'(t) =1+(2t)2            =1+4t2The distance travelled by the particle from a to b isabr'(t) dt=231+4t2dt=23t2+122dt=a2+x2dx=x2a2+x2+a22sinh-1xa=2t2t2+122+18sinh-1t1223=39+14+14sinh-1(6)-24+14+14sinh-1(4)=3372+14ln(6+37)-17+14ln(4+17)  sinh-1(x)=lnx+x2+13372-17+14ln6+374+17Thus the distance travelled by the particle from a to b is 3372-17+14ln6+374+17.