Elevator problem: energy, power, intensity,

AI Thread Summary
The discussion revolves around calculating the energy, time, and power required for an elevator with a mass of 1200 kg to ascend 100 meters. The correct energy needed is 1,176,000 Joules, calculated using the formula E = MgL, where g is 9.8 m/s². It takes 20 seconds for the elevator to rise at a speed of 5 m/s. The power supplied is calculated as P = E/t, resulting in 58.5 Watts. The initial calculations were incorrect, but the formulas used were confirmed to be accurate.
Jack Brodie
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Homework Statement


Question: An Elevator and its load have a mass of 1200 kg.
a) what energy must be supplied to lif the elevator and its load ot a height of 100m? Answer: E = _________ Joules

b)If the elevator rises at a speed of 5 m/s, how long does it take to cover 100m? Answer t= __________ sec

c) What is the power supplied? Answer P = ________ Watts


Homework Equations


Energy: E=MgL, where g=9.8m/s2 (squared) is the acceleration of gravity and Lis the distance through which a mass is moved against the force of gravity
Power: P = E/t
Intensity: I= P/A


The Attempt at a Solution



My answers:
For part a, I used the first equation (E=MgL) and I got the answer of 1176 Joules

part b: at a rate of 5 m/s it would take 20 seconds; so t = 20 seconds

Part c: P=E/t is P= 1176/20 = 58.5 watts


Does this seem right?
 
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The answer to the first one should be 1176000 Joules, but your formulas are correct.
 
Thank you for taking time to help! I appreciate it!
 
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