Question

The potential energy U in joule of a particle of mass 1kg moving in x-y plane obeys the law U= 3x+4y where (x,y) are the coordinates of the particle in metre. If the particle is at rest at (6,4) at time t=0, then find the speed of the particle when it crosses the y-axis.​​

Answer 1

Answer:

The speed of the particle when it crosses y axes is 

$10 \sqrt{3} \frac{m}{s}$

U=6x+8y

F=−6i^−8j^;a=−6i^−8j^

∣a∣=10m/s2

Sx=uxy+21axt2;−9=0−21(6)t2

t=3sec

v=u+at

v=0+(−6i^−8j^)3