How Fast Will a Block Travel After Being Pulled on a Frictionless Surface?

AI Thread Summary
A 2.7 kg block is pulled on a frictionless surface by a constant force of 17.3 N, leading to a calculated acceleration of 6.41 m/s². Since the block starts from rest, the initial velocity is 0 m/s. Using kinematic equations, the final velocity after the block moves 4 meters can be determined. The relevant equation is vf² = vo² + 2ax, which allows for the calculation of the final velocity. The discussion emphasizes the application of constant acceleration principles to solve for the block's speed.
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Homework Statement



A 2.7 kg block initially at rest is pulled to the right along a horizontal, frictionless surface
by a constant, horizontal force of 17.3 N. Find the speed of the block after it has
moved 4 m. Answer in units of m/s.

Homework Equations


a=Fnet/mass


The Attempt at a Solution


17.3N/2.7Kg=6.40741m/s now what
 
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since the force is constant , this implies that the acceleration is constant as well .. so in this case you can use one of the kinematic equations ..

vf = vo + a*t .. (vf=final velocity,vo=initial velocity,a=acceleration,t=time)
vf^2 = vo^2 +2ax (x = distance of travel)
x = vo*t + 0.5*a*t

you have now a, in the question it is said that the block initially at rest(what that tells you about the initial velocity?), you have x , I think with these quantities you can find the final velocity(in other words, the velocity after the block has moved x=4m) ..
 
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