Recent content by fterh

Can you explain how you arrived at that?

Hi, I am still unable to replicate the results in the Youtube video, although I have managed to produce a similar outcome which is equally eye-popping. Considering that I'm running out of time (I have a deadline to adhere to!), my team has decided not to waste valuable time trying to mimic the...

But how come \ N_2(1-\mu_s \tan{\theta})<0 ? Shouldn't it be: N_2(1-\mu_s \tan{\theta}) = -\frac{1}{2}mg?

Some background information: I'm doing some reading up for PhO (so it's beyond what I'm supposed to learn), and so I'll post all my questions here (regarding both concepts and actual practice questions). Sorry if you feel there is a lack of effort on my part, but sometimes I'm really lost and...

It's actually a problem from IPhO 1968.

Bump for help! :)

I need some help manipulating equations. m_1 a = m_1 g sin\alpha - \frac{aI}{r^2} - F m_2 a = m_2 g sin\alpha - \mu m_2 g cos\alpha + F From the above 2, I am able to get: a = g \cdot \frac{(m_1 + m_2) sin\alpha - \mu m_2 cos\alpha}{m_1 + m_2 + \frac{I}{r^2}} ...(1) But how do I find an...

Is this a flaw in the question? Because when it says "pulley", it's only natural to assume that rotational motion is involved, rather than frictionless sliding.

Thanks for the guidance. I guess the ratio of the diameter of the ball to the diameter of the nozzle is key here. So I'm going to play about with different sizes to see which one works. And about the pressure jump in the immediate vicinity of a powered fan/propeller, you're saying that I need...

Bump. Is 200 PPP good?

So Coanda effect dictates that the air will flow AROUND the ping pong ball (because it's attracted to the surface), while Bernoulli states that the lower pressure of the fast-moving air will cause the ball to remain stationary? I'm hoping to continue with my exhibit because the WOW factor is...

Hi guys, I'm building a science exhibit demonstrating Bernoulli's Principle for a competition. It's similar to the setup found here () at 2:51 to 2:57. So, I tried a ping pong ball and a hair blower. Doesn't work. Firstly, the hair blower is pretty weak, so when the setup is in upright...

Why is the tension in a thread the same throughout? If the pulley has a mass, a resultant torque is required to set it in rotational motion, thus the tension on one side has to be greater than the other side, no?

How do I proceed?

Okay. I've given some thought to this question and I have a question. If the backspin causes the ball to bounce back towards the left after landing at Q, won't it continue moving to the left rather than bounce back to the right towards Q (after landing at P)?