Solve Rectangular Room Mirror Homework Problem

  • Thread starter Thread starter Shibos
  • Start date Start date
  • Tags Tags
    Homework Mirror
AI Thread Summary
To solve the rectangular room mirror problem, visualize the reflection of the room as if the mirror were a window. This approach allows for straight-line diagrams, simplifying the analysis of how light travels from the person's eyes to the image of the back wall. The person standing 0.5 m in front of the mirror can see both ends of the back wall, indicating that the mirror's width and the distance from the person to the mirror are crucial for determining the wall's length. By applying geometric principles to the reflection, one can calculate the necessary dimensions. Understanding this concept is key to finding the solution.
Shibos
Messages
1
Reaction score
0

Homework Statement



A rectangular room is 6 m long. A mirror 0.35 m wide is hung on the wall horizontally at one end of the room. A person standing 0.5 m in front of the mirror can just see both ends of the back wall in the mirror. What is the length of the back wall.

I don't want the answer I just want to know how to get it. explain everything please!

Homework Equations



N/A

3. The Attempt at a Solution [/b

Don't have a clue how to attempt it.
 
Physics news on Phys.org
Welcome to PF!

Hi Shibos! Welcome to PF! :smile:

The best way to solve (flat) mirror questions is usually to draw the reflection (the image) of the room on the "wrong" side of the mirror (so that the mirror turns into a window :wink:) …

that means that instead of bent lines in your diagram, you can just draw straight lines, from the eye (on the "right" side) to the image! :biggrin:
 
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}...
I was thinking using 2 purple mattress samples, and taping them together, I do want other ideas though, the main guidelines are; Must have a volume LESS than 1600 cubic centimeters, and CAN'T exceed 25 cm in ANY direction. Must be LESS than 1 kg. NO parachutes. NO glue or Tape can touch the egg. MUST be able to take egg out in less than 1 minute. Grade A large eggs will be used.
Back
Top