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Determine Fuel Flow Engines

A turboprop engine produces a "Brake Specific Fuel Consumption" of 0.5 lb/bhp/hr. Determine the fuel flow (in kg/s) required at this bsfc to produce 800 bhp of power.

Thermodynamics - Carnot cycle problem

An air-conditioning system operating on the reversed Carnot cycle is required to remove heat from the house at a rate of 25 kJ/s to maintain its temperature constant at 20°C. If the temperatures of the outdoors is 35°C, the power required to operate this air-conditioning system is:

Sound Response Details

Hi, I need some assistance with the following physics problems. Please view the attachment to see the full set of questions.

Radioactive Decay as a Power Source

Strontium-90 is to be used in a radioisotopic thermoelectric generator (RTG) for powering a navigation beacon located in the arctic. a) How much of the Sr-90 activity is required to generate 50 W of electric power if the conversion efficiency from heat to electricity is 30%? Tip: You must take into account the fact that Sr-90

Translation operator problems.

The translation operator S(a), for arbitrary constant real vector a, is defined such that... a) Show, using the Taylor expansion of Φ(x-a) about x, that S(a) may be expressed in terms of the momentum operator p=.. Sum the expansion to give a simple closed-form expression for S(a). Please see attached for full question

Resistance and Current

The heating element of an electric broiler dissipates 2.8 kW of power when connected to a potential difference of 120 V. a. what is the resistance of the element? b. How much current does the broiler draw? use two ways to find out, and verify your answer.

Power Consumption of a Refrigerator

The Electric Meter in a House indicates that the refrigerator consumes 70.0 kWh in a week. a. What is the power consumption of the refrigerator? b. Assuming it is connected to a potential difference of 120V, how much current does the refrigerator draw?


Sam, whose mass is 75 kg, takes off across level snow on his jet-powered skis. The skis have a thrust of 200 N and a coefficient of kinetic friction on snow of 0.1. Unfortunately, the skis run out of fuel after only 10 s. What is Sam's top speed? (in meters/second)How far has Sam traveled when he finally coasts to a stop? (in me

Newton's First Law of Motion

A block with mass m has a coefficient of kinetic friction Mk with the floor. If the block is obeying Newton's 1st law while being pushed at angle 0 (theta), show that the power needed to push it at velocity v is given by P=Mkv(mg+fsin0).

Various Physics Problems

Hi, I am having trouble doing these problems listed below. Please show me how to solve these problems for future reference. Thank you very much. 1. You are told that the volume of a sphere is given by V = pie d/4, where V is the volume and d is the diameter of the sphere. Is this equation dimensionally correct? (Use SI unit

Resistors - Finding the Current

Hi. Can someone please help me with the following problem? I'll try to draw the circuit (with battery and 4 resistors), but I don't know if all the spacing will come out right. The "///" are resistors. Basically, it's a circuit with a 15-V battery and 4 resistors. First you hit R1, which = 11 ohms. Then there are two paths

RL Circuit: Calculating Power

Question: An ac generator with a frequency of 1.00 kHz and an rms voltage of 24 V is connected in series with a 2000 ohm resistor and a 0.365 H inductor. (a) What is the power factor for this circuit? (b) What is the average power consumed by this circuit?"

Power dissipation in resistors configuration

"Three resistors (R, 1/2R, 2R) are connected to a battery. (a) If the resistors are connected in series, which one has the greatest rate of energy dissipation? (b) Repeat part (a), this time assuming that the resistors are connected in parallel."

Average Power fun

Scott, riding for the Mercury team, won the 2002 Mt. Rushmore Hill Climb bicycle race with a winning time of 1 hour 50 minutes 20 seconds. The race is 28 miles in length with a total altitude gain of 7000ft. Scott weighs in at 130 lbs and his hill climbing bike weighs 17 lbs. The total weight of his water bottles, shoes, clot

Calculating resultant force and change in potential energy

The speed of a 4.0kg object is given by (2t) m/s, where t is in seconds. At what rate is the resultant force on this object doing work at t = 1 second? Answers: a) 48 W b) 40 W c) 56 W d) 16 W A 10kg object is initially at the top of a rise, at point A. It then moves down to point B. Choose point B to be your zero leve

Power Conversion Efficiencies - Practical Application

1. A steam turbine at an electric power plant delivers 4500 kW of power to an electrical generator that converts 95 percent of this mechanical energy into electrical energy. What is the current delivered by the generator if it delivers energy at 3600 V? 2. A color television draws about 2.5 A when it is connected to

Current & Resistance

1. An ant is 3 cm from a magniflying lens with a focal length of 5 cm. The image of the bug is A. real, upright, enlarged, other side of lens B. virtual, upright, enlarged, same side of lens C. virtual, smaller, inverted, same side of lens D. real, upright smaller, other side of lens A 5kW h

Wave properties of particles

The resolving power of a microscope is proportional to the wavelength used. A resolution of approximately 1.0 x 10-11 m (0.01 nm) would be required in order to "see" an atom. (a) If electrons were used (electron microscope), what minimum kinetic energy would be required for the electrons? (b) If phtons were used, what minimum p

Conducting Rod

A conducting rod of length l moves on two horizontal, frictionless rails, as shown in the attached file 'Figure P31.20'. If a constant force of 1.00 N moves the bar at 2.00 m/s through a magnetic field B that is directed into the page, (a) What is the current through the resistor R? (b) What is the rate at which energy is d

Finding work using time dependent Force function.

I only need the last five parts explained to me. See attached PDF file for the question ! Homework 5-1 Due date: Mon 22 Mar 2004 09:00:00 AM MST 18 point(s) Pulling Out Tree Stump You are in a truck trying to pull out a tree stump. The mass of the tree stump m is 170.0 kg. You have attached the winch at the f

Momentum, Velocity and Power

1. A 1500kg automobile starts from rest on a horizontal road and gains speed of 72km/h in 30 s. a) What is the average power required of the car at the end of the 30 s? b) What is the average power required of the car during the 30 s interval? c) What is the instantaneous power at the end of the 30 s interval, assuming t

Current and Power in a Resistor

A 60.0 ohm resistor is connected in parallel with a 115.0 ohm resistor. This parallel group is connected in series with a 15.0hm resistor. The total combination is connected across a 15.0-V battery. Find the current and power in the 115 ohm resistor.

Power Consumption in Europe

You buy a 60W lightbulb in Europe, where electricity is delivered to homes at 240V. If you use the lightbulb at home in the United States, how bright will it be relative to 60W 110V bulbs? Calculate how much power it will consume.

Power and Voltage Calculations

What happens to the power used by an electric appliance if the voltage across this appliance is decreased to half of the original value?