Recent content by sarahjt1

Ok... so there really isn't a homework problem that goes directly with what I am asking... I just want to understand how/why induction (magnet through a coil) gave certain results in our Science Workshop program... Here is what we did in our lab: We dropped a magnet (south end in first)...

Homework Statement The heating resistor is rated at 10ohms and 1W. By how much was its power exceeded? Why didn't the resistor burn up? This is a question taken from an Electrical Equivalent of Heat lab assignment... here is a link to the exact same lab we did...

Homework Statement file:///C:/Documents%20and%20Settings/sjthompson/Desktop/p8-3.gif Don't know if the image worked. I think if you copy and paste it into browser it might work. Calculate the net torque (mag and direction) on the beam in the figure below about the following axes. Beam has...

Nevermind... silly me. Much simpler than I thought.

Homework Statement A grinding wheel of radius 0.330m rotating on a frictionless axle is brought to rest by applying a constant friction force tangential to its rim. The constant torque produced by this force is 72.1 N*m. Find the magnitude of the friction force. I'm honestly lost at even...

Ohhh... so this is a momentum question. F delta t = mVi - mVf so... F delta t = (.0078)(575)- (.0078)(0) 2.34e4 (delta t)= 4.49 delta t = .000191 = 1.91e-4 Ah.. Thank you! I would have never of seen that relationship... grrr.

Homework Statement A 7.8g bullet moving at 575m/s penetrates a tree trunk to depth of 5.50cm. (a) Use work and energy considerations to find the average frictional force that stops the bullet. (b) Assuming that the frictional force is constant, determine hot much time elapses between the...

I got -560J as my answer but I am not sure if that is right. If it is, I don't fully understand the rationale I used to get there. I guess it is more that I don't fully understand the concepts involved. This is where my trouble lies... just in understanding the equations that are relevant to...

Homework Statement A 70 kg base runner begins his slide into second base when he is moving at a speed of 4.0m/s. The coefficient of friction between his clothes and the Earth is 0.70. He slides so that his speed is zero just as he reaches the base. a) How much mechanical energy is lost due...