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Elevator problem: energy, power, intensity,

  • #1

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?
 

Answers and Replies

  • #2
dx
Homework Helper
Gold Member
2,011
18
The answer to the first one should be 1176000 Joules, but your formulas are correct.
 
  • #3
Thank you for taking time to help!!! I appreciate it!
 

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