Power is the rate at which work is done.

Slides:

Advertisements

Similar presentations

Physics 6B Oscillations Examples Prepared by Vince Zaccone For Campus Learning Assistance Services at UCSB.

Advertisements

Practice Problem #1 A weightlifter bench presses 80kg (approx. 175lbs.) 0.75m straight up. a. How much work does she do, assuming constant velocity, in.

Physics 1D03 - Lecture 22 Energy, Work and Power.

Examples and Hints for Chapter 5

ENERGY LCHS Dr.E.

a) The kinetic energy of the car. b) The distance it takes to stop.

Dr. Jie Zou PHY 1151G Department of Physics1 Chapter 7 Work and Kinetic Energy (Continued)

1a. Positive and negative work

Mechanical Work: More Practice. Gravitational Potential Energy: More Practice.

T101Q7. A spring is compressed a distance of h = 9.80 cm from its relaxed position and a 2.00 kg block is put on top of it (Figure 3). What is the maximum.

Dr. Jie Zou PHY 1151G Department of Physics1 Chapter 7 Work and Kinetic Energy (Continued)

Example: A 20 kg block is fired horizontally across a frictionless surface. The block strikes a platform that is attached to a spring at its equilibrium.

Physics Jeopardy Work & Power Simple Machines Energy energy Extra credit on quiz questions Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400.

Tuesday, September 29, 2009 In olden days, something was only considered “doing work” if you were getting tired or sweaty doing it. Make up a definition.

Chapter 5 Work and Energy. Force, displacement  WORK.

Kinetic Energy A moving object has energy because of its motion. This energy is called kinetic energy.

Chapter 3 Energy. The Goal of this activity is to Introduce the student to the terms work, kinetic energy and gravitational potential energy, Illustrate.

High School by SSL Technologies Physics Ex-41 Click As you know, work is the product of force times the distance through which the force acts (W = Fs).

Physics 3.3. Work WWWWork is defined as Force in the direction of motion x the distance moved. WWWWork is also defined as the change in total.

Year 12 Physics Gradstart. 2.1 Basic Vector Revision/ Progress Test You have 20 minutes to work in a group to answer the questions on the Basic Vector.

Sub title Potential Energy Work Work- Energy Theorem Kinetic Energy Power 200 Work-Power-Energy.

Work-2 & Power. Work and Area If the force is constant, we can graphically interpret the work done ( W = F d ) as the area of a rectangle F tall and d.

Chapter 5 Review Mr. Hauser. Rules of the Game Working in TEAMS, you will be asked to answer questions from the assigned chapters. You have 30 seconds.

Physics 111 Practice Problem Statements 06 Work and Kinetic Energy SJ 8th Ed.: Ch. 7.1 – 7.5 Contents: 7-7E*, 7-15E, 7-19P, 7-22P, 7-23P, 7-25E*, 7-31E*,

A certain pendulum consists of a 2

Chapters 7, 8 Energy. What is energy? Energy - is a fundamental, basic notion in physics Energy is a scalar, describing state of an object or a system.

Power and Efficiency And a review of the work-energy theorem.

Energy Lecture Slide 1 Work & Energy. Energy Lecture Slide 2 Work Work = (Force in direction of motion)*distance W, Joule (J) = N-m 1 J is work done in.

Friction What is friction?. Answer Me!!! Think of two factors that affect friction.

Physics Jeopardy Free Body Diagrams 1st law2nd law Mix Up Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy.

5.4 The Work-Energy Theorem and Kinetic Energy

An 7.3-kg object rests on the floor of an elevator which is accelerating downward at a rate of 1.0 m/s 2. What is the magnitude of the force the object.

Simple Machines Power. Power: Is the rate at which work is done A machine that does a certain amount of work the fastest develops the most power Unit:

Power. Rate at which work is done P = ΔW t Measured in Watts (W) Usually seen as kW – kilowatts Horsepower (746 Watts) P = Power (Watts) ΔW = work done.

Physics 1D03 Work and Kinetic Energy Work by a variable force Kinetic Energy and the Work-Energy Theorem Power Serway & Jewett 7.3, 7.4.

PHYSICS 50: Lecture 6-1 RICHARD CRAIG. Today Exam Review Grades New Homework Chapter 6 Work, Energy and Power “Quiz”

1 Ch. 5 Work and Energy Review. 2 In which of the following actions is work not being done on the underlined object? A. A hammer strikes the head of a.

TopicSlidesMinutes 1 Displacement Vectors Kinematics Graphs Energy Springs Shadows 39 9 Field of Vision.

Energy of Simple Harmonic Motion

Chapter 7: Work and Kinetic Energy-1

Work, Power Problems Answers

1a. Positive and negative work

ENERGY EQUATIONS By the end of this presentation you should be able to: Calculate kinetic energy, work and power.

Work and Power Quiz Solutions

Midterm Review Mr. Hauser.

Work done by a variable force

Aim: How do we explain the concept of power?

AP 1 Energy practice.

Work and Power.

Ch. 6 slides.ppt Forces2.ppt.

Newton’s Laws.

Chapter 8: Potential Energy & Conservation of Energy

Engineering Mechanics

Solution... Click for answers.

Work, Energy and Power.

What do we want to do today?! Sunday:

Have you ever used Mathematica?

Have you done any work today?

Question C Force and Motion F F m F F m d d

A block of mass m resting on a horizontal

Work done = Energy Changed

A 61kW crane lifts a 1.0 ton (1000kg) mass up a height of 15.0m in 10.0s. What is the efficiency of the crane? (24%)

A 61kW crane lifts a 1.0 ton (1000kg) mass up a height of 15.0m in 10.0s. What is the efficiency of the crane? (24%)

T101-Q-1 Figure 1 shows the spring force as a function of position x for a spring-block system resting on a frictionless table. The block is released at.

Presentation transcript:

Power is the rate at which work is done.

Answer Me!!! What does it mean to be powerful?

Power Power is the rate at which work is done. Since you know that v = d/t: Power is measured in J/s or Watts (W)

Practice Problem 1 A 3 kg block is initially at rest on a frictionless horizontal surface. The block is moved 8 m in 2 seconds by the application of a 12 N horizontal force. What is the average power developed while moving the block?

Practice Problem 2 A 4.0x103 W motor applies a force of 8x102 N to move a boat at a constant speed. How far does the boat move in 16 seconds?

Practice Problem 3 A motor having a power rating of 500 W is used to lift an object weighing 100 N. How much time does the motor take to lift the object a vertical distance of 10 m?

Practice Problem 4 What is the average power developed by a motor as it lifts a 400 kg mass at constant speed through a vertical distance of 10 m in 8 seconds?

Practice Problem 6 If the time required for a student to swim 500m is doubled, the power developed by the student would be Halved Doubled Quartered Quadrupled

Final Thought… A motor having a maximum power rating of 8.1x104 W is used to operate an elevator with a weight of 1.8x104 N. What is the maximum weight the motor can lift at an average speed of 3 m/s?