Calculating Change in Kinetic Energy of 0.23kg Object

AI Thread Summary
The discussion centers on calculating the change in kinetic energy for a 0.23 kg object acted upon by a 0.50 N force, resulting in a displacement of 0.88 m. The initial confusion arises from differing results compared to the textbook, which states a final velocity of 0.89 m/s. Participants agree that the work done on the object is 0.44 J, leading to a calculated kinetic energy change of 0.44 J, which corresponds to a velocity of 1.9 m/s. The conclusion suggests a possible typo in the textbook regarding the final velocity. The conversation highlights the importance of accurate calculations in physics problems.
brad sue
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Hi I have a problem here and I am a little bit confused.

An object of mass 0.23kg is initially at tyhe origin and is acted on by the sole force F=(0.50 N)i. After a certain time, the object is at a position r=(.88m)i.
What is the change in the object's kinetic?


I tried to solve this problem by th equatiom Wnet=K, but I do not get the answer of the textbook. They found .89m/s .Apparently,it v. They did not specify.

Please can youhelp

Thank you for your time
B
 
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Sorry, this makes no sense to me! If the object moves .88 m under a .5 N force, then it has had .44 J of work done on it. It's kinetic energy should have changed by .44 J. If, as you say, that was the sole force then we should have (1/2)(.23 kg) v2= 0.44. that gives v2= 0.88/.23= 3.8 so v= 1.9 m/s.
 
HallsofIvy said:
Sorry, this makes no sense to me! If the object moves .88 m under a .5 N force, then it has had .44 J of work done on it. It's kinetic energy should have changed by .44 J. If, as you say, that was the sole force then we should have (1/2)(.23 kg) v2= 0.44. that gives v2= 0.88/.23= 3.8 so v= 1.9 m/s.

Yes, I found the same result as you.
I must have a typo in my textbook.
Thank you anyway

B
 
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