Elevator

In homes with more floor elevators are used. For passenger transport, the most commonly used traction elevator counterweight. The top of the shaft
engine room with the engine. The car is suspended on a rope, which is guided up over two pulleys to the counterweight.

Consider lift-enabled load Mmax = 300 kg
car weight mk = 500 kg
weight counterweight mz = 650 kg. Cabin moves at the speed
v0 = 1.2 m/s. The total efficiency of power is k =75%.

a) Explain what affects the efficiency of the system and the reason for using a counterweight.

b) Determine the power P1 engine lift if you summon an empty cabin residents of the upper floors, which moves down the speed of v0.
c) Determine the power P2 engine lift when a group of citizens with a total mass M = 250 kg conveys speed v0 upwards.

In which of these cases b), c) the need for more power?
g = gravitational constant 10 N/kg

Result

P1 =  2400 kW
P2 =  1600 kW

Solution:  Leave us a comment of this math problem and its solution (i.e. if it is still somewhat unclear...): Be the first to comment! Next similar math problems:

1. Trio weight Adelka, Barunka, and Cecilka are weight in pairs. Adelka with Barunka weighs 98 kg, Barunka with Cecilka 90 kg and Adelka with Cecilka 92 kg. How much does each of them weigh?
2. Shot Shot with a mass 43 g flying at 256 m/s penetrates into the wood to a depth 25 cm. What is the average force of resistance of wood?
3. Vegan shop To the shops brought together 23.2 kg of goods, fruits, vegetables and nuts. fruit was 4.7 kg more than vegetables, nuts was 1.5 kg less than the fruit. Determine the amount of fruits, vegetables and nuts.
4. Three friends Danica, Lenka and Dalibor have altogether 96 kg. Lenka weighs 75% more than Dalibor and Danica weighs 6 kg more than Dalibor. Determine the weight of Danice, Lenka and Dalibor.
5. Lee is Lee is 8 years more than twice Park's age, 4 years ago, Lee was three times as old. How old was Lee 4 years ago?
6. Chords How many 4-tones chords (chord = at the same time sounding different tones) is possible to play within 7 tones?
7. Theorem prove We want to prove the sentence: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
8. Family Family has 4 children. Ondra is 3 years older than Matthew and Karlos 5 years older than the youngest Jane. We know that they are together 30 years and 3 years ago they were together 19 years. Determine how old the children are.
9. Pooja Pooja and Deepa age is 4:5, 4 years back it was 8:11. What is the age of Pooja now?
10. Father 7 Father is 6 times older than his son. After 4 years, the father will only be 4 times older. What are their present ages?
11. Potatoes For three days the store sold 1400 kg of potatoes. The first day they sold 100 kilograms of potatoes less than the second day, the third-day three-fifths of what they sold the first day. How many kgs of potatoes sold every day?
12. Teams How many ways can divide 16 players into two teams of 8 member?
13. Friction coefficient What is the weight of a car when it moves on a horizontal road at a speed of v = 50 km/h at engine power P = 7 kW? The friction coefficient is 0.07
14. Locomotive Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done?
15. AP - simple Determine the first nine elements of sequence if a10 = -1 and d = 4
16. PIN - codes How many five-digit PIN - code can we create using the even numbers?
17. Examination The class is 21 students. How many ways can choose two to examination?