(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A particle of mass 5 kg in the x-y plane has its potential energy given by U=(-7x + 24y ) J where x and y are in metre. The particle is initially at origin and has a velocity u=(14.4i + 4.2j)m/s. Find the magnitude of force on the particle and speed of the particle at t=4s.

2. Relevant equations

3. The attempt at a solution

dU/dx=Fx

dU/dy=Fy

Therefore, Fx= -7N and Fy= 24N

Fnet = 25N

magnitude of u=15m/s

magnitude of acceleration=25/5=5m/s^2

Hence v=15+5x4=35m/s

But the answer is 25m/s

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# Homework Help: Potential Energy And Force

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