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 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 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
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.
Because that was a mistake. Good catch!
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
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
👍👍💯💯
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
Bhai kati zhr
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: th-cam.com/video/h_rnqo7XB2U/w-d-xo.html
Cheers,
Dr. A
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