force, work, energy and power - ms finnegan's science...
TRANSCRIPT
![Page 1: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/1.jpg)
Force, work,
energy and
power
![Page 2: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/2.jpg)
Matter and Mass
Mass = Amount of matter in something
Matter = Anything that takes up space
and has a mass
![Page 3: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/3.jpg)
Force A Force is a push or a pull to get
something to move
Force = Mass x Acceleration (gravity)
Gravity is always 10 m/s2
Force = Mass x 10 m/s2
![Page 4: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/4.jpg)
Units of Force are Newtons (N)
Example of forces are gravity, electricity
and magnetism
Force can also be known as weight
Weight = Mass x Gravity (10 m/s2)
![Page 5: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/5.jpg)
Iassac Newtown
![Page 6: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/6.jpg)
Difference between mass
and weight
We have a mass and weight on earth but
only a mass in space
We only have a weight when we are
exposed to gravity
![Page 7: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/7.jpg)
Calculate the weight of a book that has
a mass of 1.5 kg?
Weight = Mass x Gravity
![Page 8: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/8.jpg)
Weight = 1.5 kg x 10 m/s2
Weight = 15 N
![Page 9: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/9.jpg)
Calculate the weight of an object with
mass 6 kg
Weight = Mass x Gravity
![Page 10: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/10.jpg)
Weight = 6 kg x 10 m/s2
Weight = 60 N
![Page 11: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/11.jpg)
Calculate the force acting on a book of
mass 1.2 kg
Force = Mass x Gravity
![Page 12: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/12.jpg)
Force = 1.2 kg x 10 m/s2
Force = 12 N
![Page 13: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/13.jpg)
Friction Friction is a force that tries to stop or slow
down a moving object
Friction - Can be reduced by smooth
surfaces or by using a lubricant like oil or
grease
![Page 14: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/14.jpg)
Advantages of Friction Friction between our shoes and the
ground stops our feet slipping backwards.
Friction between car tyres and the road
stops the car skidding
![Page 15: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/15.jpg)
Disadvantages of Friction Wears brake pads on cars
Need more fuels in cars
![Page 16: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/16.jpg)
![Page 17: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/17.jpg)
Experiment to investigate
Hooke’s Law Hooke’s Law states that the extension of a
spring is directly proportional to the force
applied to it.
You use a spring balance. This will tell you
the force acting on the spring and also
the extension of the spring
![Page 18: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/18.jpg)
Apply weights to the spring balance in an
increasing order
Record the weight and the distance on
the spring
Plot a graph of your results
![Page 19: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/19.jpg)
Initial Set Up Add a weight and
measure the length that
the spring stretched.
Repeat for different
weights and record in a
chart.
![Page 20: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/20.jpg)
Weight / g 0 49 98 147 196
Extension of Spring /
cm 0 2 4 6 8
![Page 21: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/21.jpg)
![Page 22: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/22.jpg)
Use the graph to estimate what force
results in the spring extension of 7 cm
Use the graph to estimate the spring
extension when the force is 49 N
Does this graph obey Hookes law?
![Page 23: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/23.jpg)
Work Work = Force x Distance
The unit for work is Joules (J)
![Page 24: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/24.jpg)
A force of 100N moves an object 50m in
the direction of the force. What is the
work done by the force?
Work = Force x Distance
![Page 25: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/25.jpg)
Work = Force x Distance
Work = 100 N x 50 m
Work = 5000J
![Page 26: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/26.jpg)
Calculate the work done when a force of
30 N moves an object 50 m
Work = Force x Distance
![Page 27: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/27.jpg)
Work = Force x Distance
Work = 30 N x 50 m
Work = 1500J
![Page 28: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/28.jpg)
Energy Energy is the ability to do work.
So the unit for energy is Joules (J)
![Page 29: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/29.jpg)
Power Power = Work Done___
Time Taken
Unit of Power: Watts (W)
![Page 30: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/30.jpg)
Calculate the power when it takes a
person 10 seconds to carry out 50 Joules
of work
Power = Work Done___
Time Taken
![Page 31: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/31.jpg)
Power = Work Done___
Time Taken
Power = 50 J___
10 s
Power = 5 W
![Page 32: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/32.jpg)
A crane lifts a weight of 5000N a vertical
distance of 2m in 4s. What is the power
needed?
We need two things to calculate power
![Page 33: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/33.jpg)
Work and Time
Time = 4 seconds
Work = ?
Work = Force x Distance
Work = 5000 N x 2 m
Work = 10,000J
![Page 34: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/34.jpg)
Power = Work Done___
Time Taken
Power = 10000 J___
4 sec
Power = 2,500 Watts
![Page 35: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/35.jpg)
It takes a person 5 seconds to lift a weight
of 4000 N vertically 5 m. What power is
needed?
Power = Work Done___
Time Taken
![Page 36: Force, work, energy and power - Ms Finnegan's Science Websitemsfinneganssciencewebsite.weebly.com/.../14133966/force_work_an… · Energy Energy is the ability to do work. ... Calculate](https://reader035.vdocuments.us/reader035/viewer/2022070907/5f822e8b126030634d23bcd2/html5/thumbnails/36.jpg)
Work = ?
Time = 5 seconds
Work = Force x Distance
Work = 4000 N x 5 m
Work = 20,000 Joules
Power = 20,000 J___
5 sec
Power = 4,000 Watts