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VikaD [51]
3 years ago
6

Which of the following is a chemical change?

Physics
1 answer:
klemol [59]3 years ago
3 0

a). Water is still H₂O after it freezes.

b). Ice is still H₂O after it melts.

c). Wire is still Cu when it's bent.

d). Paper combines with the O₂ in the air, and turns into
     a lot of new compounds when it burns.

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A student uses the right-hand rule as shown.
Kipish [7]

Answer:

right is the correct answer to the given question .

Explanation:

In this question figure is missing

The main objective right-hand rule to decide the position of the magnetic force on the positive force acting, either the position of the thumb of a right hand with in position of v, the fingers throughout the position of B1, and a right angles throughout the position of F1 to the hand positions.

So    F1 \ =\ q\ v \ B1\ Sin\alpha

  • So from the magnetic right hand rule the direction of the magnetic field in front of a wire is right .
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3 years ago
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What does direction of force mean?
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The direction of an arrow shows the direction of the force, and the length of the arrow indicates the amount, or size, of the force.
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3 years ago
The law of conservation of mass states that _______________________________.
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Energy cannot be created nor be destroyed
3 0
3 years ago
A 7kg block slides down a 30 degree slope at a constant velocity of 2 m/s. How big is the force of friction acting on the block?
lisabon 2012 [21]

The force of friction is <u>34.3 N.</u>

A block of mass m slides down a plane inclined at an angle θ to the horizontal with a constant velocity.  According to Newton's first law of motion, every body continues in its state of rest or a state of uniform motion in a straight line, unless acted upon, by an external unbalanced force. This means that when balanced forces act on a body, the body moves with a constant velocity.

The free body diagram of the sliding block is shown in the attached diagram. Resolve the weight mg of the block into two components  mg sinθ along the direction of the plane and mg cosθ perpendicular to the plane . The force of friction   F acts upwards along the plane  and the normal reaction acts perpendicular to the plane.

Since the block moves down with a constant velocity, the downward force mg sinθ must be equal to the upward frictional force.

F = mg sin\theta

Substitute 7 kg for m, 9.8 m/s² for g and 30° for θ.

F = mg sin\theta = (7 kg)(9.8 m/s^2)(sin30^o) =34.3 N

The force of friction is <u>34.3 N</u> up the plane.


6 0
4 years ago
Help with ALL PLZZZz
Vika [28.1K]
I can't read the ones on the top but, 7. Is D which you put lol and I believe what you put for 9. is right and 10. I believe your answer is H aka C lol Hope this helps!!! :D
4 0
3 years ago
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