Physics - Mechanics: Applications of Newton's Second Law (12 of 20) There is a Mistake in this Video

[@twinstarsnz3626]

Sorry, but if the load on one end of the rope is = to the load on the other one = T/2, it means that these are = to one another. Therefore the tension on one end cannot definitely be 1/2 the load. If you were right, it could be the Force doubles the load instead of viceversa!! Thanks

[@MichelvanBiezen]

+John Reacher I believe you caught an error. Parts a, b, and c are correct, but I'll have to rework part d. Thanks

[@twinstarsnz3626]

You are anyway a great man!! Thanks for your lessons!!

[@ajaygrewal5354]

sir could you explain the free body diagram of box ,actually i want to know the effect of pulling the rope on the box

[@makeislameasy4206]

Me too

[@NM-zb6pd]

Answer to part D has to be (M+m)(g+a)/2 = (368 + (75/2)) N 1. F-Mg-R = Ma 2. F+R-mg = ma Adding 2 gives F = (M+m)(g+a)/2

[@mohammadtaheri2304]

Thank you my dear , i think when a=0 F=(m+M)g=(15+25)9.8=392N then T=2f=784N When a=2 F-(m+M)g=(m+M)a F-(15+25)9.8=(15+25)2 F-392=80 F=472 T=2F T=944 N

[@daniyalravandeh5223]

Thanks for your video. However, I guess that there is a not really accurate assumption about the guy and the box as if we consider another person in the box as heavy as the other one (50kg) while he/she doesn't pull any rope and he/she is only standing in the, then we would have: Box weight: 9.8*(25+50)=735N And the guy with rope in hand will meet the box ceiling as he/she weighs lighter than the 735N as follows: The guy with rope in hand weight: 9.8*50=490N And it doesn't depend on T (Total tension where the pulley is attached to rigid body)

[@fahmidaferdousi6844]

Thank you for posting these videos! They help a lot. I have a question at 5:29 min into the video: how come for part d, you didn't take half of (m1+m2)a? When you showed T/2 = 1/2(m1+m2)g in part a, was it because the equation was set up as 1/2(T-mg) = 1/2(ma), where 1/2(ma) went to zero since there was zero acceleration or was it set up as 1/2(T-mg) = ma? Part d seems like you did 1/2(T-ma) = ma and that doesn't make sense to me.

[@fahmidaferdousi6844]

'm' being the total mass of the person and the chair, sorry.

[@MichelvanBiezen]

Fahmida Ferdousi The T/2 is in reference to the tension at the top where the pulley is connected to the ceiling. Draw a free body diagram around the pulley and you'll get that result. Use F = ma and you'll get the answer in the video.

[@youssefgebah]

this problem is really tricky i couldn't wrap my head around it logically

[@MichelvanBiezen]

Tricky indeed.

[@youssefgebah]

still, you are a very great man I really like solving problems with you. I can't tell you how much you helped me throughout the chapters@@MichelvanBiezen