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2 years ago

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A railroad freight car of mass 3.34 × 104 kg collides with a stationary caboose car. They couple together, and 19.0% of the init

ial kinetic energy is transferred to thermal energy, sound, vibrations, and so on. Find the mass of the caboose.

1 answer:

Tresset [83]2 years ago

8 0

Answer:

4.123 * 10∧4 kg

Explanation:

mass of car M' = 3.34 * 10∧4 kg

energy loss E = 19/100 K

from law of conservation of momentum ,

M' V' = ( M' + M'' ) v

V = M' V' / ( M' + M'' )

Initial kinetic energy is K' = (M' V')² / 2

final kinetic energy K" = 81 K' /100

= (M' V')² 81 / (200) = ( M' + M'' ) v²/ 2

therefore , M' / ( M' + M" ) = 0.81

mass of caboose is , M" = 1.234 M' - M'

M" = .234 M'

= 0,234 ( 3.34 * 10∧4 kg)

= 4.123 * 10∧4 kg

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