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Nikolay [14]
2 years ago
11

Jamie pushes a book off a table. The push is an example of a contact force because A. Jamie used energy. B. Jamie had to touch t

he book to move it. C. the book fell to the floor. D. the book was on a flat surface.
Physics
2 answers:
gizmo_the_mogwai [7]2 years ago
6 0
From the word "contact" clearly defines it as touch. three types of forces: contact -  field -  electro-static. thus the answer is C : Jamie hd to touch the book to move it'
 
olasank [31]2 years ago
3 0

Explanation :

Contact forces are the forces that act between the objects that are in contact.

When James pushes a book off a table, the push is an example of a contact force. This is because Jamie had to touch the book to move it. For experiencing a contact force, there should be contact between two objects.

The examples of contact forces are the frictional force, tension force, normal force etc.

While gravitational force, electric force and the magnetic force are non contact force.

So, the correct option is (B) " Jamie had to touch the book to move it ".

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Irina18 [472]

Answer:

(b) 10 Wb

Explanation:

Given;

angle of inclination of magnetic field, θ = 30°

initial area of the plane, A₁ = 1 m²

initial magnetic flux through the plane, Φ₁ =  5.0 Wb

Magnetic flux is given as;

Φ = BACosθ

where;

B is the strength of magnetic field

A is the area of the plane

θ is the angle of inclination

Φ₁ = BA₁Cosθ

5 = B(1 x cos30)

B = 5/(cos30)

B = 5.7735 T

Now calculate the magnetic flux through a 2.0 m² portion of the same plane

Φ₂ = BA₂Cosθ

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Therefore, the magnetic flux through a 2.0 m² portion of the same plane is is 10 Wb.

Option "b"

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2 years ago
Consider an alcohol and a mercury thermometer that read exactly 0 oC at the ice point and 100 oC at the steam point. The distanc
Alexeev081 [22]

Answer:

No, both the thermometers will give the different reading.

Explanation:

Given,

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3 0
2 years ago
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dimaraw [331]

Answer:

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where B is the magnetic field and A is the area

Let's look at stationary, for which factors affect flow

* The value of the magnetic field changes either in time or space

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