energy. work motion direction motion must be in the same direction of the apply force
TRANSCRIPT
WORK, DISTANCE AND FORCE
Energy
Work
Motion
Direction
Motion must be
in the same
direction of the
apply force.
Units
Force Distance work
Newton (N) Meter (m) Joules (J)
Equation
Work Distance force
w= F x d D = w/f F = w/d
Potential energy
Energy store or waiting for being use. Potential energy cannot be transferred.
Kinetic energy
Motion, movement
Kinetic energy can be transferred from one moving object to another.
Kinetic Energy Potential Energy
Sound Gravitational (GPE)
Mechanical (objects move)
Mechanical (objects in position…ready)
Radiant (electromagnetic spectrum)
Nuclear (energy stored in nucleus)
Thermal (heat) Chemical (stored in particles)
Electrical
We have been taught that:
Every (Electrical)
Child (Chemical)
Knows (Kinetic)
Pork (Potential - Gravitational. lift. Or elastic. spring)
Sausages (Sound)
Have (Heat)
No (Nuclear)
Legs (Light)
Work done = Force x _______
distance acceleration velocity speed
Units
Force Distance work
Newton (N) Meter (m) Joules (J)
Equation
Work Distance force
w= F x d D = w/f F = w/d
1 joule = 1 _______
N m2
Kg . m2/s2
N m N2 m2
Which form of energy does the flowing water possess?.
gravitational energy potential energy electrical energy kinetic energy
A coolie carries a load of 500 N to a distance of 100 m. The work done by him is _________.
5 N 50,000 Nm 0 1/5 N
The type of energy possessed by a simple pendulum, when it is at the mean position is
1. kinetic energy 2. potential energy 3. potential energy + kinetic energy 4. sound energy
According to the scientific definition of work, pushing on a rock accomplishes no work unless there
movement. a net force. an opposing force. movement in the same
direction as the direction of the force.
Which of the following is a form of energy that is a kind of potential energy?
radiant Electrical Chemical none of the above
Potential energy cannot be transferred.
Electrical energy can be converted to:
chemical energy. mechanical energy. radiant energy. any of the above.
Units
Force Distance work
Newton (N) Meter (m) Joules (J)
Equation
Work Distance force
w= F x d D = w/f F = w/d
Most all energy comes to and leaves the earth in the form of
nuclear energy. chemical energy. radiant energy. kinetic energy.
The law of conservation of energy is basically that _________.
energy must not be used up faster than it is created or the supply will run out.
energy should be saved because it is easily destroyed.
energy is never created or destroyed. you are breaking a law if you
needlessly destroy energy.
The most widely used source of energy today is:
A) coal. B) petroleum. C) nuclear. D) water power.
Which quantity has the greatest influence on the amount of kinetic energy that a large truck has while moving down the highway?
A) mass
B) weight
C) velocity
D) size
Which of the following statements is / are CORRECT?
Inter-conversion of kinetic energy and potential energy is only valid in the system of roller coaster and simple pendulum.
A hydroelectric power plants use the inter-conversion of kinetic energy and potential energy to generate electricity.
We can make use of conservation of energy to create energy.
A construction worker holds a heavy tool box. How much work is done by the worker?
FGd FGd mgh ½ mv2 zero
An example of Kinetic Energy would be:
a moving car a stretched rubber band
that was just released a charge particle in an
electric field all of the above
Units
Force Distance work
Newton (N) Meter (m) Joules (J)
Equation
Work Distance force
w= F x d D = w/f F = w/d
An example of Potential Energy would be:
a moving car a battery a book resting on a table both b and c
Which is not an example of Solar Radiation
Microwaves Magnetism gamma rays visible light
An example of a system having both kinetic and potential energy would be:
a book resting on a table a piece of sugar an object in free fall a stretched rubber band
Which of the following statements is not correct
energy is the capacity to do work
Work can be express as Force x Distance
power is the amount of work done in a unit of time
the unit of power is the joule1.
A horizontal force of 200 N is applied to move a 55 kg television set across a 10 m level surface. What is the work done by the 200 N force on the television set?
550 J 6000 J 2000 J 11000 J
A child pulls a balloon for 12 m with a force of 1.0 N at an angle 60 below horizontal. How much work does the child do on the balloon?
–10 J 6.0 J –6.0 J 12 J
Which of the following energy forms is associated with an object due to its position?
potential energy total energy positional energy kinetic energy
How much work would this 10 N force acting over 10 m do on a 10 kg object?
a) 0 J b) 70.7 J c) 100 J d) 980 J e)1000 J
A 10 kg mass is held 1.0 m above a table for 25 s. How much work is done during that
10 J 250 J 9.8 J 980 J none
A rock weighing 10 newtons is lifted a distance d from the ground. The work done by the force that lifts the rock is 10 joules. The rock is then dropped on a wooden stake, thus driving the stake into the ground. The distance d is most nearly _________.
0.01 m0.1 m1 m10 m100m
Solve using all procedure
How much work is done on a bookshelf being pulled 5.00 m at an angle of 37.0 from the horizontal? The magnitude of the component of the force that does the work is 43.0 N.
W= f x d= 43.0N x 5.00N215J
Potential or Kinetic?
Running in a marathon. Car in the parking lot Air across the classroom Pencil over the desk Eat candy
KPKPk
How much work is done when a 5 N force moves a block 4 m?
w = f x d
= 5N x 4m
= 20J
6. How much work is done when a 100 N force moves a block 59 m?
w = f x d
= 100N x 59m
= 5,900J
7. Fred applies 350 N of force to move his stalled car 40 m, How much work did Fred do?
w = f x d
= 350N x 40m
= 14,000J
8. You move a 25 N object 5 m. How much work did you do?
w = f x d
= 25N x 5m
= 125J
9. You carry a 20 N bag of dog food up a 6 m flight of stairs. How much work did you do?
w = f x d
= 20N x 6m
= 120J
11. How far will 350 J raise a block weighing 7 N?
Far = distance D = w ÷ f or D = w/f D = w/f
= 350J/7N
= 59m
12. How far will 350 J raise a block weighing 15 N?
D = w/f
= 350J/15N
= 23.33333333333333m
= 23.33m round to the nearest hundredths
13. Which is more work, pushing with 115 N over 15 m or lifting 20 N 10 m?
w = f x d w = f x d
= 115N x 15m = 20N x 10m
= 1725J = 200J
Pushing
14. Which is more work, pushing with 115 N over 15 m or lifting 200 N 10 m?
w = f x d w = f x d = 115N x 15m = 200N x 10m
= 1725J = 2000Jlifting
15. Write the units of force, distance, work
W= Joules (J) F = Newton (N) D= meter (m)