An electric lift is required to raise a load of 5 tonne through a height of 30 m. One quarter of electrical energy supplied to the lift is lost in the motor and gearing. Calculate the energy in kWh supplied. If the time required to raise the load is 27 minutes, find the kW rating of the motor and the current taken by the motor, the supply voltage being 230V d.c. Assume the efficiency of the motor at 90%.

An electric lift is required to raise a load of 5 tonne through a height of 30 m. One quarter of electrical energy supplied to the lift is lost in the motor and gearing. Calculate the energy in kWh supplied. If the time required to raise the load is 27 minutes, find the kW rating of the motor and the current taken by the motor, the supply voltage being 230V d.c. Assume the efficiency of the motor at 90%.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

See similar textbooks

Similar questions

A dc transmission facility is modeled by the approximate series circuit shown below. If the load voltage is known to be Vload= 458.3 kilovolt (kV) what is the power loss in the line in megawatt (MW)? what is the voltage at the source Vs in kilovolt? Write two(2) decimal places in your answer.
Incremental fuel costs in dollars per megawatthour for a plant consisting of two units are given by:dC(P)/dP = 0.0080 P1 + 8.0dC(P)/dP = 0.0096 P2 + 6.4Assume that both units are operating at all times, that total load varies from 250 to 1250 MW, and that maximum and minimum loads on each unit are to be 625MW and 100MW respectively. Find the incremental fuel cost and the allocation of load between units for the minimum cost of various total loads.Write your answers in the given format below.
Estimate the AEP for a 3-MW wind turbine in a wind regime that has a CF= 30%. For this turbine explain why the increase of wind speed to levels greater than 25 m/s generates less electrical power compared to wind speeds around 11 m/s
Discuss the significance of power factor in electrical power systems and methods for improving it.
MERALCO Electrician has a 25 kW series generator used in street lighting has anefficiency of 85 % when operating at rated load. If the stray power loss is 20 %of the full load loss, calculate the efficiency of the generator when delivering aload of 15 kW, assuming that the stray power loss is substantially constant andthe other losses vary as the square of the load.
A diesel-electric power plant is operated by an industrial firm to supply its daily power requirements. During the 24-hour operation, the fuel consumption is 315 gallons and produces average energy of 3,150 kW-hrs. The fuel used is 25 API at 30°C and the cost is P50.00 per liter at 15.6°C. The generator efficiency is 90% and the mechanical efficiency is 85%. Determine the brake heat rate in kJ/kW-hr,
The following data are given for a wind turbine: Blade length, l = 45 m Wind speed, U = 12 m/sec Air density, r = 1.25 kg/m3 Find the following: a) Total wind power in MW that can be extracted b) Maximum wind turbine power in MW that can be generated c) Actual wind turbine power in MW if the power coefficient is 0.38 d) Blade tip speed in m/s if the rotational speed is 7 rpm e) Tip speed ratio
You want to buy electric energy. You can buy from company A, B, C, or D,but you must choose only one. You obtain past data on these four suppliers, and you then determinethat the prices for some of them have been quite volatile, influenced by the state of the economy(recession, stagnation, and inflation). You assess this data given in the table below. Assuming that you simply want to minimize your average costs over the long run, determine theexpected costs for all energy suppliers. Select the supplier based on minimum expected cost.
A 100MW hydro-electric station is supplying full load for 10 hours in a day. The water is supplied from a reservoir of 1km2 surface area. Calculate the reduction in the water level of the reservoir in one day. Assume effective head of water as 200 m and efficiency of the the station is 80%.
Pls answer thank you! A hydro power plant is to be used as peak load plant at an annual load factor of 30%. The electrical energy obtained during the year is 750 x 105 kWh. Determine the maximum demand. If the plant capacity factor is 24% find reserve capacity of the plant in KW.
Asap, select the best answer In dc machine, which among the parts converts the AC voltage into its equivalent DC voltage? A. commutator B. brushes C. Yoke D. Field poles
A dc transmission facility is modeled by the approximate series circuit shown below. If the load voltage is known to be Vload= 458.3 kilovolt (kV) what is the power loss in the line in megawatt (MW)? Write two(2) decimal places in your answer.