Momentum Conservation in Collisions - How to Solve for Resulting Velocity

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SUMMARY

The discussion focuses on solving a physics problem involving the conservation of momentum in a completely inelastic collision between two trucks. The first truck weighs 1500 Newtons and travels at 45.0 m/s at an angle of 105 degrees, while the second truck weighs 1800 Newtons and travels at 27.5 m/s at 55 degrees. To find the resulting velocity of the combined trucks post-collision, the mass of each truck is calculated using the formula mass = force / gravity (9.8 m/s²). The momentum conservation principle is applied, requiring calculations for both x and y components of the momentum vectors.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Knowledge of momentum and its conservation
  • Ability to perform vector addition
  • Familiarity with basic physics equations, including F = mg
NEXT STEPS
  • Study the principles of completely inelastic collisions
  • Learn how to decompose vectors into their x and y components
  • Explore examples of momentum conservation in two-dimensional collisions
  • Practice calculating resultant velocities from multiple collision scenarios
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Students studying physics, particularly those focusing on mechanics and collision problems, as well as educators seeking to explain momentum conservation in real-world scenarios.

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I'm confused on how to start this Physics problem. Please help me and go through the steps with me.
Thank you.

Two trucks collide. One weighed 1500 Newton and was traveling 45.0 m/s at 105 degrees. The second weighed 1800 Newton and was traveling 27.5 m/s at 55 degrees. Find the resulting velocity of the trucks if they stuck together on impact

Ok so the first step i did was get the mass which is the force (1500) divided by 9.8 m/s^2 and got 150 kg and did the same to truck #2 and got 180 kg.
Because i know we have to use the mass to find the momentum which is force time velocity.

However after that step what i do?
 
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The setup will be one of a completely inelastic collision:$$m_{1}v_{1} + m_{2}v_{2} = (m_{1} + m_{2}) v$$This means that the sum of the individual momenta will equal the momentum of the combined masses. However, since this problem is in two dimensions, you need to use the equation twice: once for the x-components of velocity, and again for the y-components.
 
Hello lover and welcome to PF. A special welcome, I might add, because the nickname fills us with (false?) pride.

Somehow you managed to evade the template. But your rendering of these toy trucks smacking into one another gives me the impression you've seen it come by. Please use it next time.

Now to business: One of the relevant equations would be F = mg which you used to calculate the m. Decently written exercise: weight as a force. We like that.
Another would be conservation of momentum. You should have learned that momentum is conserved in accidents like this. Momentum is not force times velocity, but mass times velocity. masses you have, velocities you have also. Note that velocities are vectors: they have a magnitude (given) and a direction (also given). All you have to do is add these momentum vectors to get the momentum vector of the stuck-together wreckage, of which you can easily calculate the mass. Divide by mass and voila: the velocity vector !
 

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