Calculating Heat Capacity for Cage Weight of 1000 kg at 9 m/s

AI Thread Summary
To calculate the oil required to maintain a bearing temperature of 70°C while raising a 1000 kg cage at 9 m/s, the work done by friction must be equated to the heat energy produced. The relevant equations involve calculating the work done using the linear motion equation and the force due to gravity. The heat energy can then be derived from the specific heat capacity of the oil, which is 2100 J/kg K. The attempt to solve the problem involves finding the distance and subsequently using it to determine the mass of oil needed. Clarification on the calculations and methodology is sought to confirm correctness.
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Homework Statement


in the absense of bearing friction a winding engine would raise a cage weighing 1000 kg at 10m/s, but this is reduced by friction to 9 m/s, how much oil, initially at 20 C is required per second to keep the temperature of the bearing down to 70 C
(specific heat capacity of oil is 2100 J/Kg K , g = 9.81 )


Homework Equations



heat energy = mass x specific heat capacity x change of temperature

The Attempt at a Solution



i personally do not know how to attempt this question, i was trying to see if there is any relationship between velocity and energy, but i couldn't find anything. please .. help
 
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The work done by friction is equal to the energy released as heat. Calculate the work done by friction using conservation of energy, then go from there.
 
RobL14 said:
The work done by friction is equal to the energy released as heat. Calculate the work done by friction using conservation of energy, then go from there.

first of all, thank you very much, but yet still i didnt get the correct answer. therefore i would like to find out if i was in the right direction

1. by using linear motion equation : v^2 = u^2 +2as
solved for S : s = v^2-u^2/2a

when distance is found. i calculated the force = mg

word done by the friction is equal to the heat energy therefore : force = mg x S

since heat energy is found. equation ... Heat energy = m c ( theta temp ) was used
solve for mass
M = heat energy / c ( theta temp.)
am i correct?
 
first of all, thank you very much, but yet still i didnt get the correct answer. therefore i would like to find out if i was in the right direction

1. by using linear motion equation : v^2 = u^2 +2as
solved for S : s = v^2-u^2/2a

when distance is found. i calculated the force = mg

word done by the friction is equal to the heat energy therefore : force = mg x S

since heat energy is found. equation ... Heat energy = m c ( theta temp ) was used
solve for mass
M = heat energy / c ( theta temp.)
am i correct?
 

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