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

1.A 6kg block slides down a frictionless incline making an angle of 60 degree with the horizontal.(a) What is the speed of the block after it has slid 1.5 if it starts from rest. (b) What is its speed after 1.5m if it starts with an initial speed of 2 m/s ?

2. A single force of 5 N acts in the x direction on an 8kg object. (a) If the object starts from rest at x=0 at time t=0, find its velocity v as a function of time.(b) write an expression for the power input as a function of time.(c) What is the power input of the force at time t= 3s

2. Relevant equations

W=KE

F=ma

3. The attempt at a solution

1. I use W=Kinetic energy to find v. I found down that Wtotal= Wgravity + Wnormalforce=102N.

Then I set 102=1/2 mv^2. But I got marked wrong. Any opinion ??

2. I use F=ma to find the acceleration then use acceleration as the slope of V(t) but I am wrong again. How should I do this ?

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# Homework Help: Force and energy problems

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