Power Equations: 9th Grade Physics Help

  • Thread starter Thread starter Tool
  • Start date Start date
  • Tags Tags
    Power
AI Thread Summary
The discussion focuses on a 9th grader seeking help with power equations in physics, specifically how to calculate power using resistance and voltage, as well as current and voltage. Key equations mentioned include P=IV, I²R, and V²/R. One participant offers to share a scan of an Ohm's Law chart that contains various relationships relevant to the topic. Contact information is exchanged for sending the chart via email. The conversation emphasizes collaboration and resource sharing among students for better understanding of physics concepts.
Tool
Messages
2
Reaction score
0
hello, I am in the 9th grade and i have forgoten some equations for Physics. I need to know the equations to find power if given resistance and voltage, current and voltage, etc. I know P=IV but I am not sure on the equations for the different instances. Any help would great.
 
Physics news on Phys.org
I know of two others: Theres I^2 R, and V^2 / R . I have a little Ohms Law chart somewhere. I could find it and send you a scan of it if you want. I think it has about a dozen of the relationships on it.
 
could u email it to me?
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top