Hockey puck momentum/ collision

  • Thread starter Thread starter miamirulz29
  • Start date Start date
  • Tags Tags
    Collision Momentum
AI Thread Summary
A 7 kg hockey puck moving at 3 m/s collides with a stationary identical puck on frictionless ice, resulting in two pucks moving at angles of 41.1647 degrees and 48.8353 degrees. The momentum conservation equation is applied, considering both x and y components of the collision. The initial calculations for the speed of the first puck after the collision yielded an incorrect result due to a calculator error. After identifying the mistake, the correct speed was determined to be 1.844 m/s. The discussion emphasizes the importance of accuracy in calculations during physics problems.
miamirulz29
Messages
62
Reaction score
0

Homework Statement


A puck of mass 7 kg moving at 3 m/s strikes an identical puck that is stationery on frictionless ice. After the collision, the first puck leaves with a speed of v1 at an angle of 41.1647 degrees with respect to its original line of motion and the second puck leaves with a speed of v2 at 48.8353 degrees.


Homework Equations


MaVa + MbVb = MaVa' + MbVb'

The Attempt at a Solution


Puck along x-axis:
MVa = MVa' * Cos 41.1647 + MVb' * Cos -48.8353

y-axis:
0 = MVa' * Sin 41.1647 + MVb' * Sin -48.8353


I solved for Va' and got 1.844 (rounded to 3 decimal places), but that answer is wrong. What did I do wrong?
 
Physics news on Phys.org
Figured it out. Calculator error.
 
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...
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}...
Back
Top