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3 years ago

Why are the action and reaction forces described by Newton’s third law of motion excluded in the free-body diagram of an object?

Physics

2 answers:

Lorico [155]3 years ago

6 0

The correct answer is:

B. They act on different objects, so they would not appear together.

Let's take for example a box sitting on a table. If we draw the free-body diagram of the box, we would draw two forces:

- the weight of the box (downward)

- the normal reaction of the table on the box (upward)

However, this is not a pair of action-reaction forces as described in Newton's third law. In fact, the correct action-reaction pair would be:

- weight of the box (=gravitational force exerted by the Earth on the box)

- gravitational force exerted by the box on the Earth

We see that these two forces act on two different objects (the first one on the box, the second one on the Earth), so they do not appear in the same free-body diagram.

umka2103 [35]3 years ago

4 0

B. <span>They act on different objects, so they would not appear together.</span>

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3 years ago

Assuming a vertical trajectory with no drag, derive the applicable form of the rocket equation for this application

VARVARA [1.3K]

Answer:

The vertical trajectory is governed by Ordinary Differential Equation.

Time derivatives of each state variables.

d(d)/dt = v, d(m)/dt = -d(m-fuel)/dt, d(v)/dt = F/m.

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The two sign cases in derivative equations above are required because F is defined positive up, so the drag D and thrust T can subtract or add to F depending in the sign of V . In contrast, the gravity force contribution mg is always negative. In general, F will be some function of time, and may also depend on the characteristics of the particular rocket. For example, the T component of F will become zero after all the fuel is expended, after which point the rocket will be ballistic, with only the gravity force and the aerodynamic drag force being p

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4 years ago

The process by which the gene in the nucleotide suddenly changes its position is called.

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Mutation is the process by which the gene in the nucleotide suddenly changes its position

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Learn more about DNA at brainly.com/question/16099437

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2 years ago

two cars are moving at constant speeds in a straight line along a major highway. The first is travelling at 20ms^-1 and the seco

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Answer:

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3 years ago