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bogdanovich [222]
3 years ago
13

An object is at rest on the ground. The object experiences a downward gravitational force from Earth. Which of the following pre

dictions is correct about why the object does not accelerate downward? Select two answers. Justify your selections.A) The bonded molecules of the object are repelled upward by the bonded molecules of the ground with the same magnitude as the gravitational force downward on the object.B)The normal force is exerted upward on the object from the ground with the same magnitude as the gravitational force downward on the objectC) The bonded molecules of the object are attracted downward by the bonded molecules of the ground with the same magnitude as the gravitational force downward on the object.D) The force of friction is exerted upward on the object from the ground with the same magnitude as the gravitational force downward on the object.
Physics
2 answers:
Montano1993 [528]3 years ago
6 0

Answer:

A) and B) are correct.

Explanation:

If the object is at rest, it means that no net force is exerted on it.

As the object experiences a downward gravitational force from Earth, in order to be at rest, it must experience an upward force with the same magnitude as the gravitational force on the object.

This force is supplied by the normal force, which can adopt any value in order to meet the condition imposed by Newton´s 2nd Law, and is always perpendicular to the surface on which the object is placed (in this case, the ground).

At a molecular level, this normal force is supplied by the bonded molecules of the ground that behave like small springs being compressed by the molecules of the object, exerting an upward restoring force upward on them.

So, the statements A) and B) are true.

KIM [24]3 years ago
4 0

Answer:

The bonded molecules of the object are repelled upward by the bonded molecules of the ground with the same magnitude as the gravitational force downward on the object.

The normal force is exerted upward on the object from the ground with the same magnitude as the gravitational force downward on the object.

Explanation:

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I'm not positive but if I'm reading the question right it would be the big bang sorry if I'm wrong

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If the engine receives 6.45 kJ of heat energy from the reservoir at 520 K in each cycle, how many joules per cycle does it rejec
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Answer:

3.72 kJ

Explanation:

QH = 6.45 kJ

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By use of Carnot's theorem

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3 years ago
A 2.00 kg cat is in a 97.00 kg elevator. What force on the elevator cable would be needed to lower the cat/elevator pair with an
umka21 [38]

The magnitude of force on the elevator cable that would be needed to lower the cat/elevator pair is 198 Newton.

<u>Given the following data:</u>

  • Mass of cat = 2 kg
  • Mass of elevator = 97 kg
  • Acceleration = 2 m/s^2

To determine the magnitude of force on the elevator cable that would be needed to lower the cat/elevator pair, we would apply Newton's Second Law of Motion:

First of all, we would calculate the total mass of the cat/elevator pair.

Total \;mass=2 + 97

Total mass = 99 kilograms

Mathematically, Newton's Second Law of Motion is given by this formula;

Force = mass \times acceleration

Substituting the given parameters into the formula, we have;

Force = 99 \times 2

Net force = 198 Newton

Read more here: brainly.com/question/24029674

3 0
3 years ago
Two charged point particle are located at two vertices of an equilateral triangle and the electric field is zero at the third ve
Debora [2.8K]

Answer:

Option E

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In the presence of two point charges at the two vertices of an equilateral triangle, the resultant electric field at the third vertex due to these charges can not be zero whether the charges are identical or not.

The reason being that only of the x or y component of the field can be cancelled out in either case still the total field can't be reduced to zero.

This can only be achieved if another charge is present.

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Ultravoilent rays is an type of an electromegnetic wave with wavelength 10nm .Ultraviolet wave is used by doctors in order to keep the wounds away from bacteria.

<h3>What is ultravoilent wave ?</h3>

Ultravoilent rays is an type of an electromegnetic wave with wavelength 10nm. Ultravoilent wave is directly comes frim the sun. It is classified into the UV(A) , UV(B),UV(B).

Ultravoilet rays also effects the human eyes that s why sun glasses are used. The experiments here are compared and quantified to the effectiveness of the sunscreens with various strengths.

To learn more about the ultravoilent wave refr to the link;

brainly.com/question/19706211

5 0
2 years ago
Read 2 more answers
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