Power. Power Power is defined as “Work per unit time”

Slides:



Advertisements
Similar presentations
The rate at which work is done.
Advertisements

6-7 Problem Solving Using Conservation of Mechanical Energy
Work & Energy Chapter 6 (C&J) Chapter 10(Glencoe).
Power The rate at which work is done. Objective: To define and apply the concepts of power and mechanical efficiency.
Module 11 Movement and change.
Work, power and energy(2)
What can you remember from P3 in Y11? Definition Definition Formula Formula Derived Units Derived Units Actual units Actual units.
Dynamic Electricity: Electric Energy &Power. Electric Power The electric power of a machine is an indication of the amount of work it can do, that is,
Energy, Work, Power, and the Law of Conservation of Mechanical Energy You are studying the most critical and looked out for issue in todays world.
Introduction to Work Monday, September 14, 2015 Work Work tells us how much a force or combination of forces changes the energy of a system. Work is.
ENERGY Part I.
Chapter 6.  Energy is “conserved” meaning it can not be created nor destroyed Can change form Can be transferred  Total energy does not change with.
Energy and Conservation Physics Chapter 5-2 (p ) Chapter 5-3 (p )
How much work does a 154 lb. student do when climbing a flight of stairs that are 6 meters in height and 30 meters in length? If the stairs are climbed.
Work and Kinetic Energy Teacher: Luiz Izola
Energy m m Physics 2053 Lecture Notes Energy.
Mechanics 105 Work done by a constant force Scalar product Work done by a varying force Kinetic energy, Work-kinetic energy theorem Nonisolated systems.
What is Energy? Physics Definition: The ability to do work Work: Force applied over a distance (W =f*d) Force: From Newton, force is the product of a mass.
Goal: To understand Energy Objectives: 1)To learn about What energy is 2)To learn about Work 3)To learn about Power 4)To understand the relationships and.
Chapter 6 (C&J) Chapter 10(Glencoe)
Physics Spring  Go Over Friction Quest ◦ Take the Friction Quest if missing yesterday  Second Semester Review Assignment  Notes: Work.
Sect. 8-7: Gravitational Potential Energy & Escape Velocity.
Chapter 6.1 Notes Power. The time it takes to complete an activity is as important as the work required. Compare running up stairs to walking up stairs.
Warm up 1) How much energy does a 45 kg rock have when it is at the top of a 70 m cliff? 2) How much energy does a 20 kg tricycle have when it is moving.
Work and Energy.
Work WORK is done only if a force F causes an object to move a distance D. WORK = F  D The units for work are Newton- meters (Nm) or Joules (J). 1 Nm.
Acceleration. Acceleration – The rate at which velocity changes Results from a change in speed and direction Acceleration = change in velocity = Δv timet.
V P Power, force and velocity Power is the rate at which a force does work. The SI unit of power is the watt (W) 1 W is the rate f working of 1 J s -1.
What is Energy? Physics Definition: The ability to do work Work: Force applied over a distance (W =f*d) Force: From Newton, force is the product of a mass.
Work&EnergyWork&Energy. 4.1 Work Done by a Constant Force.
5.4 The Work-Energy Theorem and Kinetic Energy
Kinetic and Potential Energy UCR MESA. What is Energy? What does it mean if you have a lot of energy? For students it means you can run around, lift weights.
Power Chapter 5.6 WOD is underlined. Question A 2400 kg car can slow from 10 m/s to rest in 3.2 meters.If the car has traditional friction brakes, what.
What is Energy? Physics Definition: The ability to do work Work: Force applied over a distance (W =f*d) Force: From Newton, force is the product of a mass.
Section 4 Conservation of Energy. I. Energy Transformations PE = mgh PE = (515 kg)(9.8 m/s 2 )(70.0 m) PE = 353,290 J At the top of the hill, PE is at.
Chapter8: Conservation of Energy 8-7 Gravitational Potential Energy and Escape Velocity 8-8 Power HW6: Chapter 9: Pb. 10, Pb. 25, Pb. 35, Pb. 50, Pb. 56,
Acceleration. Acceleration – rate at which velocity changes Results from a change in speed and direction Acceleration = change in velocity = Δv timet.
Chapter 5 Power 1. Power is the rate at which work is done. More generally, power is the rate of energy transferred by any method. 2.
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.
Chapter 13 Energy and Work Section 4 Power. Power Power is the rate at which work is done or the amount of work done in a unit of time. Power is the rate.
Unit 5: Work, Power and Energy. Work Work is done when a force causes a change in motion of an object, or work is a force that is applied to an object.
Physics 101: Lecture 10, Pg 1 Physics 101: Lecture 10 Potential Energy & Energy Conservation l Today’s lecture will cover Textbook Sections Hour.
Acceleration.
Work and Energy Objectives: Work done by Forces Power
Conservation of Energy
Solving Problems with Energy Conservation.
Section 3 Falling Objects
Power.
Kinetic and Potential Energy
Kinetic and Potential Energy
Power & Efficiency.
SC100 Class 5 Homework Assignment
Power.
Acceleration.
Power - The rate at which work is done
Section 6.3 Differential Equations
Work and Energy Power.
Power Power is the amount of work applied over a period of time
POWER Is the rate at which work is performed. P = work/time = Watt
Acceleration.
Power.
CHAPTER 15: ENERGY!.
Work Work is the bridge between Force and Energy..
Free Fall.
Practice for FA5.2.
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%)
Physics 1 – Jan 6, 2017 P3 Challenge– Today’s Objective: Power
Presentation transcript:

Power

Power is defined as “Work per unit time”

Power is defined as “Work per unit time” Units: 1 J/s = 1 W (Watt) (1 hp = 746 W)

Power Power is defined as “Work per unit time” Units: 1 J/s = 1 W (Watt) What does the “Power Company” sell you?

Power Power is defined as “Work per unit time” Units: 1 J/s = 1 W (Watt) What does the “Power Company” sell you? What is a “kilowatt-hour”?

A light bulb consumes 3600 J of electrical energy every minute that it’s on. What is the power rating of this light bulb? A) 36 W B) 60 W C) 100 W D) 360 W E) 3600 W

When a person runs up a flight of stairs, she does work mgh When a person runs up a flight of stairs, she does work mgh. The power she generates depends on how long it takes to go from the bottom to the top. h

When a person runs up a flight of stairs, she does work mgh When a person runs up a flight of stairs, she does work mgh. The power she generates depends on how long it takes to go from the bottom to the top. Let’s do it! h

When passing a tractor on the highway, you accelerate your 1 When passing a tractor on the highway, you accelerate your 1.80 x 103 kg car from 26.8 m/s to 31.5 m/s in 2.75 s. What power is required to do this?

While the engine is doing positive work on the car, friction and air resistance are doing negative work. K engine The rate at which friction and air resistance do work depends on the speed of the car. When they are doing work at the same rate, the car’s speed won’t change. A higher power engine allows the engine to do work at a higher rate, allowing for a higher top speed. heat

As a car drives up a hill, it has to overcome gravity, friction, and air resistance. The power required to do that depends on velocity… (It’s a bit more complicated than it looks, since air resistance goes up with speed or speed2)

It takes a force of 1450 N to keep a 1300 kg car moving with constant speed up a slope of 5.25˚. If the engine delivers 4.10 x 104 W (55 hp) to the drive wheels, what is the maximum speed of the car?