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5 votes
While a dog runs forward, its

owner pulls back with a 22.4 N
force at a 115º direction, doing
-42.3 J of work. How far did the
dog move?
(Unit = m)
HELP ME

2 Answers

4 votes

Answer:

Step-by-step explanation:

the person on top of me is right it’s 4.47

User Jay Wang
by
7.0k points
4 votes

Answer:

d = 4.47 [m]

Step-by-step explanation:

To solve this problem we must make a free body diagram, where we can see the direction of the force acting with the appropriate angles. In the attached image we can see the free body diagram mentioned.

So in the image, we can see an angle of 65° with respect to the horizontal, therefore we can calculate the horizontal component of the force.

Fx = 22.4*cos (65)

Fx = - 9.46 [N] (it's negative because the force is pointing in the negative direction).

We can obtain the same result using 115° as the angle.

Fx = 22.4*cos (115)

Fx = 9.46 [N]

Now we know that work is defined as the product of the force by the distance, therefore we have.

Note: Always the work must be calculated with the force parallel

to the movement

W = F*d

Where:

W = work = 42.3 [J] (units of joules)

F = force parallel to the movement = 9.46 [N]

d = distance [m]

d = W/F

d = 42.3/9.46

d = 4.47 [m]

While a dog runs forward, its owner pulls back with a 22.4 N force at a 115º direction-example-1
User Maxbeaudoin
by
6.3k points