What is the Kinetic Energy of Bullets Fired at Different Speeds?

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SUMMARY

The kinetic energy of bullets fired at different speeds can be calculated using the formula EK = (1/2)mv². For a 3.5g bullet fired at 42.4 m/s, the correct kinetic energy is 3.14 Joules after converting the mass to kilograms (0.0035 kg). The initial calculation of 3235.968 was incorrect due to failure to convert grams to kilograms. The second bullet, fired at 69.6 m/s, would require a similar calculation for its kinetic energy.

PREREQUISITES
  • Understanding of kinetic energy formula EK = (1/2)mv²
  • Knowledge of unit conversion from grams to kilograms
  • Basic physics concepts related to motion and energy
  • Familiarity with calculating squares of numbers
NEXT STEPS
  • Learn about unit conversions in physics, specifically mass from grams to kilograms
  • Explore the implications of kinetic energy in real-world applications
  • Study the effects of speed on kinetic energy using different masses
  • Investigate other forms of energy and their calculations, such as potential energy
USEFUL FOR

Students studying physics, educators teaching energy concepts, and anyone interested in the practical applications of kinetic energy calculations.

PepeF.
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Homework Statement



two 3.5g bullets are fired with speeds of 42.4 m/s and the 2nd one with 69.6 m/s

what is the kinetic energy of the first bullet?
the second one?


Homework Equations



EK=(1/2)mv^2

The Attempt at a Solution



EK=(1/2)3.6*42.4^2 = 3235.968

it is wrong.. why?
 
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you have not converted the mass of the bullet from grams to kgrams

0.50 x (3.5x10^-3) x 42.4^2 = 3.14J

this is the answer i got
 

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