Force and Work Unit Test
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Question
A person pushes a box. He applies a force of 400 newtons, and he pushes the box for a distance of 4 meters. After he stops pushing, the box slides forward another meter. How much work was done by the person?(1 point)
Responses
100 joules
100 joules
2,000 joules
2,000 joules
1,600 joules
1,600 joules
400 joules
400 joules
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Yes, I apologize for the mistake earlier. The correct answer is:
class 1 = F, E, L (or L, E, F)
class 2 = L, F, E (or E, F, L)
class 3 = E, F, L (or L, F, E)
So, the correct answer is: class 1 = F, E, L (or L, E, F), class 2 = L, F, E (or E, F, L), class 3 = E, F, L (or L, F, E).
The correct answer is 1,600 joules. Work is calculated using the formula W = Fd, where W is work done, F is the applied force in newtons, and d is the distance moved in meters. In this case, W = 400 N x 4 m = 1,600 J. The additional meter the box slides does not affect the work done by the person, as they are not applying a force during that distance.
Force and Work Unit Test
2 of 122 of 12 Items
Question
Use the diagram of the pulley system to complete the statement.
An illustration shows a system of two pulleys lifting a block.
In this pulley system, the pulleys will _____ the mechanical force required to lift the block and will change the _____.
(1 point)
Responses
increase; direction of the force
increase; direction of the force
increase; weight of the block
increase; weight of the block
decrease; weight of the block
decrease; weight of the block
decrease; direction of the force
decrease; direction of the force
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The correct answer is decrease; direction of the force. Pulleys are simple machines that can be used to change the direction of a force and/or decrease the amount of force required to lift an object. In this pulley system, the pulleys will decrease the mechanical force required to lift the block and will change the direction of the force. By using two pulleys, the force required to lift the block is cut in half, making it easier to lift.
Which list correctly orders effort (E), fulcrum (F), and load (L) for each lever class?(1 point)
Responses
class 1 = F, E, L (or L, E, F)
class 2 = L, F, E (or E, F, L)
class 3 = F, L, E (or E, L, F)
class 1 = F, E, L (or L, E, F), , class 2 = L, F, E (or E, F, L), , class 3 = F, L, E (or E, L, F)
class 1 = F, L, E (or E, L, F)
class 2 = F, E, L (or L, E, F)
class 3 = L, F, E (or E, F, L)
class 1 = F, L, E (or E, L, F), , class 2 = F, E, L (or L, E, F), , class 3 = L, F, E (or E, F, L)
class 1 = F, E, L (or L, E, F)
class 2 = F, L, E (or E, L, F)
class 3 = L, F, E (or E, F, L)
class 1 = F, E, L (or L, E, F), , class 2 = F, L, E (or E, L, F), , class 3 = L, F, E (or E, F, L)
class 1 = L, F, E (or E, F, L)
class 2 = F, L, E (or E, L, F)
class 3 = F, E, L (or L, E, F)
class 1 = L, F, E (or E, F, L), , class 2 = F, L, E (or E, L, F), , class 3 = F, E, L (or L, E, F)
can u pls answer my question?
thank you
You're welcome! Let me know if you have any other questions.
How do simple machines make work easier?(1 point)
Responses
They decrease the distance needed between a person and an object, allowing the person to apply more force and do more work.
They decrease the distance needed between a person and an object, allowing the person to apply more force and do more work.
They increase the distance over which a force is needed, doing more work with less force.
They increase the distance over which a force is needed, doing more work with less force.
They magnify the force being applied, thereby decreasing the work they can do with no extra energy exerted by the person using the machine.
They magnify the force being applied, thereby decreasing the work they can do with no extra energy exerted by the person using the machine.
They reduce the amount of force needed to move an object to do the same amount of work.