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g A 48.7 g clay, moving at 9.8 m/s, crashes into 1.1 kg brick that is sitting at rest on a frictionless surface. After the collision, the clay is stuck to the brick. This is an inelastic collision, where some kinetic energy (for the system of both masses) is lost. How much kinetic energy is lost (so your answer will be negative!)

User Kasbah
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1 Answer

5 votes

Answer:

-2.2394181 J amount of kinetic energy is lost.

Step-by-step explanation:

Let Vf be the final speed

(48.7) (9.8) = (48.7 + 1100) Vf

477.26 = 1148.7 Vf

=> Vf = 0.4155 m/s

KE initiali = 1/2 (0.0487) (9.8)²

KE initial = 1/2 (0.0487) (96.04)

KE initial = 1/2 (4.677148)

KE initial = 2.338574 J

KE final = 1/2 (1.1 + 0.0487) (0.4155)²

KE final = 1/2 (1.1487‬) (0.17264025)

KE final = 1/2 (0.198311855175)

KE final = 0.0991559 J

KE (lost) = KEf - KEi

= 0.0991559 J - 2.338574 J

= -2.2394181 J

User Jon Hulka
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6.3k points