Find the work done by a force f of 21 pounds acting in the direction < 2,5> in moving an object 7 feet from (0,0) to (7,0).

Please find the attachment for a better understanding of the solution provided here.

We have been asked to find the work done by a force F of 21 pounds acting in the direction <2,5> in moving an object 7 feet from (0,0) to (7,0).

As we can see clearly from the question above that the object moves exclusively in the direction of the x axis and thus, the component of the force acting is only the x component. So, our main aim will be to find the x component of the force. Once it is found we will simply multiply it with the distance travelled in the x axis to find the work done as asked in the question.

Let us call the x component of the force as .

From the diagram in the attachment, we can see that the degrees

Thus, feet

feet-pound

Thus, A is the correct option

Work done, W =  54.59 foot-pounds

Step-by-step explanation:

It is given that,

Force, F = 21 pounds

From the figure it is clear that,

Distance, d = 7 feet

Work done is given that,

W = 54.59 foot-pounds

So, the correct option is (A).

Hence, this is the required solution.

a. is correct

x = 2

step-by-step explanation:

if sr parallel to ba then the sides bc and ac are in proportion, that is

= ← substitute values

= ( cross- multiply )

27x = 6(4x + 1)

27x = 24x + 6 ( subtract 24x from both sides )

3x = 6 ( divide both sides by 3 )

x = 2