I know it was three years ago but I definitely should have read the comments xD... I spent a good ten minutes redoing my work to see why I wasn't getting 24m/s
I like how the kinematic equation Vf = Vo + at just falls out of the impulse concept. The latter is obviously more powerful since the force applied doesn't have to be constant.
Pretty cool, eh. Note: Here we used a constant force so we could bring it out of the integral, and then of course we end up with a kinematic equation. If the force is not constant, then you can't bring it out of the integral, you don't get constant acceleration, and you can't use the kinematic equations. Cheers, Dr. A
I am confused about this situation where in a cart there is a bob hanging through a string and a bullet hits the bob horizontally ( the cart is open from one end) so will momentum be conserved in cart + bob + bullet system or just in bob + bullet....i thought that momentim will be conserved in first system but in the solution givwn in my book they chose second system and i sont understand why
Because that was a mistake. Good catch!
How did you get 24 m/s using (2.5-.98)(10) ?
I got 15.2 m/s
I know it was three years ago but I definitely should have read the comments xD... I spent a good ten minutes redoing my work to see why I wasn't getting 24m/s
Did you ever do (like) a water jet on a wall or like air molecules on a piston? Ie, a high collision rate?
No, I'll have to put that on the to do list. Great idea.
Cheers,
Dr. A
I like how the kinematic equation Vf = Vo + at just falls out of the impulse concept. The latter is obviously more powerful since the force applied doesn't have to be constant.
Pretty cool, eh.
Note: Here we used a constant force so we could bring it out of the integral, and then of course we end up with a kinematic equation. If the force is not constant, then you can't bring it out of the integral, you don't get constant acceleration, and you can't use the kinematic equations.
Cheers,
Dr. A
yep. that what I meant by the last bit. Thanks for all of these vids. Very helpful, esp I'm just learning this stuff on my own for fun.
in the first problem, could we use newton's second law and find a, a=F/m=2.5 m/s^2
then v_f=v_i+a*t=a*t=2.5*10=25 m/s... we get the same thing
+ig ml
Ig,
Absolutely you can! Well done.
Cheers,
Dr. A
I am confused about this situation where in a cart there is a bob hanging through a string and a bullet hits the bob horizontally ( the cart is open from one end) so will momentum be conserved in cart + bob + bullet system or just in bob + bullet....i thought that momentim will be conserved in first system but in the solution givwn in my book they chose second system and i sont understand why
This is what you want: ruclips.net/video/h_rnqo7XB2U/видео.html
Cheers,
Dr. A
Bhai kati zhr
Cheers,
Dr. A
👍👍💯💯
Vishal Rao,
Thanks for the comment, and keep up with the physics!
You might also like my new website: www.universityphysics.education
Cheers,
Dr. A