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urp:physgen [2021-10-18]
nerf_herder
urp:physgen [2022-02-01]
nerf_herder [Newton's 3 laws]
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-==== General Physics ==== +===== General Physics =====
-  * [[#​Newton'​s 3 laws]] +
-  * [[#​Distance,​ time, velocity, acceleration]] +
-  * [[#​Collisions]] +
-  * [[#Inclined plane]] +
-  * [[#Spring and lever]] +
-  * [[#​Projectile fired at an angle]] +
-  * [[#Buoyant force]] +
-  * [[#​Gravity]] +
-  * [[#​Kinematics]] +
-  * [[#​Miscellaneous]]+
  
 ====Newton'​s 3 laws==== ====Newton'​s 3 laws====
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 Basic definitions:​ Basic definitions:​
-  * Force is in newtons or pounds. One newton = 1kg * m / s² (the force needed to accelerate 1kg at 1 m/s²)+  ​* **Force** is in newtons or pounds. One newton = 1kg * m / s² (the force needed to accelerate 1kg at 1 m/s²)
     * f = ma     * f = ma
-  * Momentum is p+  ​* **Momentum** is p
     * p = mv     * p = mv
-  * energy ​work (joules) = force * distance+  ​* **energy ​or work** (joules) = force * distance
     * J = F*d = applying 1 newton for 1 meter (units of kg * m²/s²)     * J = F*d = applying 1 newton for 1 meter (units of kg * m²/s²)
     * F = J/d     * F = J/d
 +    * Work is positive if it is applied in the same direction as movement
 +    * No (net) work is done moving an object horizontally some set distance (unless you overcome friction) - it does not gain or lose potential energy, or have increased kinetic energy at the conclusion
 +  * **power** = work/time (joules/sec or watts) ​
  
 Fnet = Δp / Δt (since p = mv and Δv/Δtime = acceleration) Fnet = Δp / Δt (since p = mv and Δv/Δtime = acceleration)
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   When parallel force > friction, it is unbalanced and objects will move down the plane   When parallel force > friction, it is unbalanced and objects will move down the plane
   Applied force - friction = net force   Applied force - friction = net force
 +
 +====Friction====
 +Coefficient of friction ​
 +  * μ = f/N  (force applied divided by Normal force)
 +  * fNet = fApp - Ffriction
  
   static friction -    static friction - 
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           N = normal force) must be overcome before the mass moves           N = normal force) must be overcome before the mass moves
     μS = fs/N = m*g*sin(θ) / m*g*cos(θ) = sin(θ)/​cos(θ) = tan(θ)     μS = fs/N = m*g*sin(θ) / m*g*cos(θ) = sin(θ)/​cos(θ) = tan(θ)
-  kinetic friction - normal ​moving friction+  kinetic friction - moving friction
    only one type of friction applies at a time    only one type of friction applies at a time
  
-====Spring and Lever==== 
-**Hooke'​s law** for springs: F=-kx, k=spring constant, x = displacement 
- 
-**Fulcrum**:​ t = r * f  (torque = radius * force) 
-just add the torques for multiple objects on one side of a fulcrum 
  
 ====Projectile fired at an angle==== ====Projectile fired at an angle====
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     vf²= vo² + 2ad     vf²= vo² + 2ad
     vf = v0 + at     vf = v0 + at
 +
 +
 +====Optics====
 +Refraction on going into a different medium
 + 
 +**Snell'​s law** 
 +   ​sin(θ₁) / sin(θ₂) = v₁/v₂ = n₂/​n₁ ​ (note that the n values are reversed)
 +   v = velocity of light in that medium, n = index of refraction
 +   v = c/n  (c = speed of light in a vacuum)
 +   it bends towards the normal direction when entering denser material
 +   (and slows down). bend is because photons are waves.
 +   
 +   ​Critical angle : smallest angle that results in total reflection, no refraction
 +   θc = arcsin(n₂/​n₁)
 +
  
 ====Miscellaneous==== ====Miscellaneous====
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 DV = dependent variable - the variable measured (changes because of the experiment) y axis DV = dependent variable - the variable measured (changes because of the experiment) y axis
  
 +FBD = free body diagram - a drawing of mass and all the forces that are applied to it.
  
 Back to the [[physics]] page or the [[00_start|start]] page. Back to the [[physics]] page or the [[00_start|start]] page.
urp/physgen.txt · Last modified: 2022-02-01 by nerf_herder