Subjects

Sections | |||
---|---|---|---|

Intro to Energy | 15 mins | 0 completed | Learn |

Intro to Calculating Work | 36 mins | 0 completed | Learn |

Work By Gravity & Inclined Planes | 40 mins | 0 completed | Learn |

Work By Variable Forces (Springs) | 47 mins | 0 completed | Learn |

Net Work & Kinetic Energy | 39 mins | 0 completed | Learn |

More Work-Energy Problems | 39 mins | 0 completed | Learn |

Power | 20 mins | 0 completed | Learn |

Solution: An energy-efficient lightbulb, taking in 28.0 W of power, can produce the same level of brightness as a conventional lightbulb operating at power 100 W. The lifetime of the energy-efficient bulb is 10

An energy-efficient lightbulb, taking in 28.0 W of power, can produce the same level of brightness as a conventional lightbulb operating at power 100 W. The lifetime of the energy-efficient bulb is 10 000 h and its purchase price is $4.50, whereas the conventional bulb has a lifetime of 750 h and costs $0.42. Determine the total savings obtained by using one energy-efficient bulb over its lifetime as opposed to using conventional bulbs over the same time interval. Assume an energy cost of $0.200 per kilowatt-hour.

Air resistance at high speed is often given as Fa...

A car moves at a speed of 25 m/s. If the car were...

Your friend (mass 65.0 kg) is standing on the ice ...

When the 210-kg Genesis Mission capsule crashed w...

A 68 kg human sprinter can accelerate from rest t...

A 20.0-kg rock is sliding on a rough, horizontal s...

A pump is required to lift a mass of 810 kg of wa...

The Grand Coulee Dam is 1270 m long and 170 m high...

An 80 kg football player traveling 5.0 m/s is st...

Six dogs pull a two-person sled with a total mass ...

A 1300 kg sports car accelerates from rest to 90 ...

You may want to review (Pages 189 - 191).
For re...

For a physics lab experiment, four classmates run
...

The hammer of a pile driver weighs 3800 N and must...

You may want to review (Pages 222 - 223).How much ...

In a hydroelectric dam, water falls 30.0 m and th...

When its engine of power 76 kW is generating full...

An elevator has mass 600 kg, not including passeng...

A hydroelectric power plant uses spinning turbines...

A
95 kg
firefighter needs to climb the sta...

How long will it take a 1800 W motor to lift a 33...

A ski area claims that its lifts can move 44000 pe...

What is the average power output of an elevator th...

Water flows over a dam at the rate of 560 kg/s an...

A 70 kg hiker climbs to the top of a 4300 m -high...

A fire hose for use in urban areas must be able to...

Some electric power companies use water to store e...

The motor of a crane uses power P to lift a steel ...

If a volcano spews a 500 kg rock vertically upwar...

Your job is to lift 30-kg
crates a vertical dis...

A typical flying insect applies an average force e...

The aircraft carrier John F. Kennedy has mass 7.41...

When you ride a bicycle at constant speed, nearly ...

If a car generates 21 hp when traveling at a stea...

A driver notices that her 1180 kg car slows down ...

An outboard motor for a boat is rated at 65 hp .If...

A tandem (two-person) bicycle team must overcome a...

The total consumption of electrical energy in the ...

It is not unusual for a 1000-kg car to get 30 mi/...

At midday, solar energy strikes the earth with an ...

Astronomers using a 2.0-m-diameter telescope obser...

All birds, independent of their size, must maintai...

A physics student spends part of her day walking b...

How much work can a 5.0 hp motor do in 2.0 h ?

On December 27, 2004, astronomers observed the gre...

Six diesel units in series can provide 13.4 MW of ...

It takes a force of 51 kN on the lead car of a 16...

If 12.0 hp are required to drive a 1800-kg automo...

A farmer uses a tractor to pull a
190 kg
b...

A 80 kg skier grips a moving rope that is powered...

A bicyclist of mass 75 kg (including the bicycle) ...

In a common test for cardiac function (the "stress...

A ski tow operates on a slope of angle 15.1 of le...

A 10 kg object slides along a surface with a coeff...

How much work must you do to push a 12.0 kg block ...

It is 6.00 km from your home to the physics lab. A...

(a) How much energy is consumed by a 1.2 kW hair d...

An 820-N Marine in basic training climbs a 12.0-m ...

During a workout, football players ran up the stad...

A bicyclist coasts down a 6.5 degree hill at a ste...

A test car of mass 740 kg is moving at a speed of ...

Four students run up the stairs as shown in the fi...

The electric motor of a model train accelerates th...

Sewage at a certain pumping station is raised vert...

A certain rain cloud at an altitude of 1.75 km con...

An electric scooter has a battery capable of suppl...

A 3.50-kN piano is lifted by three workers at cons...

A pump lifts 23.0 kg of water per minute through a...

While running, a person transforms about 0.600 J o...

When an automobile moves with constant speed down ...

An energy-efficient lightbulb, taking in 28.0 W of...

For saving energy, bicycling and walking are far m...

The mass of a car is 1 500 kg. The shape of the ca...

A loaded ore car has a mass of 950 kg and rolls on...

Enter your friends' email addresses to invite them:

We invited your friends!

Join **thousands** of students and gain free access to **55 hours** of Physics videos that follow the topics **your textbook** covers.