Calculating Momentum of a 50g Bullet: Need Help?

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SUMMARY

The discussion focuses on calculating the momentum of a 50g bullet with a kinetic energy of 250J. The relevant formulas include momentum (P = mv) and kinetic energy (Ek = mv²/2). To find the momentum, one must first derive the velocity (v) from the kinetic energy formula. The change in momentum is determined by the bullet's mass and its velocity, which can be calculated once the velocity is known.

PREREQUISITES
  • Understanding of basic physics concepts, particularly momentum and kinetic energy.
  • Familiarity with the formulas for momentum (P = mv) and kinetic energy (Ek = mv²/2).
  • Knowledge of how to manipulate algebraic equations to solve for unknowns.
  • Basic understanding of impulse and its relation to momentum (FT = ΔP).
NEXT STEPS
  • Learn how to derive velocity from kinetic energy using the formula Ek = mv²/2.
  • Study the relationship between force, time, and momentum change (FT = ΔP).
  • Explore practical examples of momentum calculations in different physics scenarios.
  • Review additional resources on kinetic energy and momentum from reputable physics websites.
USEFUL FOR

Students studying physics, educators teaching mechanics, and anyone interested in understanding the principles of momentum and kinetic energy calculations.

Recce
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(Mentor's Note: Thread moved from general physics after being replied to, hence the lack of a template)

Find the momentum of a 50g bullet whose kinetic energy is 250J.
I know the formula to find momentum is P= mv. Please give me hints
 
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Can you find "v" from what you've been given?
 
Bystander said:
Can you find "v" from what you've been given?
No, the question only gave me 50 g bullet and 250J
 
You have been given a definition/formula for kinetic energy?
 
Th
Bystander said:
You have been given a definition/formula for kinetic energy?
The formula the teacher gave are p=mv and FT= delta P
 
Recce said:
p=mv
This is the definition of momentum, and you've indicated you understand it.
Recce said:
FT= delta P
"Force x time (which is impulse) equals change in momentum." The bullet before it is fired has zero velocity and zero momentum. The change in momentum then is just "mv" from the first definition. So, all you need to find now is force and time.

Are you absolutely certain you haven't been given any other definitions or formulas for kinetic energy, force, mass, work?
 
Bystander said:
This is the definition of momentum, and you've indicated you understand it.

"Force x time (which is impulse) equals change in momentum." The bullet before it is fired has zero velocity and zero momentum. The change in momentum then is just "mv" from the first definition. So, all you need to find now is force and time.

Are you absolutely certain you haven't been given any other definitions or formulas for kinetic energy, force, mass, work?
No
 
Kinetic energy is defined as Ek = mv2/2 . I cannot believe that you haven't seen this in class or in the teaching materials or textbooks before being asked the original question.
 
Recce said:
No

The problem gives mass and kinetic energy.

Find the momentum of a 50g bullet whose kinetic energy is 250J.

You should know what kinetic energy is. Look after in your lecture notes. Or you can browse the Net. See, for example: http://www.physicsclassroom.com/class/energy/u5l1c.cfm
 
  • #10
(Attached image removed by moderator, provided the answer to the OPs homework question.)

-----------------------

Örsan Yüksek
 
  • #11
Correct!
 

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