Find Work, W, done by a force, F, of 14 lbs acting in the direction of (3,4) and moving on object 7 ft
A w= 485
B w=137
C w=97
D w=59
The correct answer was 59ftlbs
Vector review practice
1. B (14,-5)(66,7)
2. A Sqrt 22^2+4^2
3. B (4,12)
4. D Yes same mag and direction
5. D V and u neither… 0,90,180
6. C 4mi 56 degrees
7. A 174mph …. 58 northeast
8. A -200
9. D 59 ft•lbs
10. C 4/5i-3/5j
You’re welcome I missed some but these are the correct answers have a nice day 🌸
eh is 100% correct, thanks pookie
Thank you for sharing the correct answers! Have a great day too! 🌸
You're welcome! It's my pleasure to assist you.
To find the work done by a force, you can use the formula:
W = F * d * cos(theta)
where:
W = work done (in joules or newton-meters)
F = magnitude of the force (in newtons or pounds)
d = displacement (in meters or feet)
theta = angle between the force and displacement vectors
In this case, we have:
F = 14 lbs
d = 7 ft
theta = angle between the force and displacement vectors
To find the angle between the force vector and displacement vector, you can use the dot product formula:
cos(theta) = (F dot d) / (|F| * |d|)
where:
F dot d = dot product of F and d
|F| = magnitude of F
|d| = magnitude of d
In this case, we have:
F = (3,4)
d = 7 ft
Now, let's calculate the dot product and magnitudes:
F dot d = (3 * 7) + (4 * 0) = 21 + 0 = 21
|F| = sqrt((3^2) + (4^2)) = sqrt(9 + 16) = sqrt(25) = 5
|d| = 7 ft
Next, calculate the angle using the formula:
cos(theta) = (21) / (5 * 7)
Now, calculate the work done using the formula:
W = 14 lbs * 7 ft * cos(theta)
Finally, substitute the values into the equation and calculate the work done:
W = 98 * cos(theta)
To determine the value of cos(theta), we need to find the value of theta. However, with the given information, we cannot determine the angle between the force and displacement vectors. Therefore, we cannot calculate the exact value of work done.
As a result, we cannot determine the correct answer among options A, B, C, and D.
If the motion is in the direction of the force
then 14 * 7 = 98 ft pounds
However you did not specify the direction of the motion.
You imply that the force is in direction 3 i + 4 j but you did not actually say that. You did not even hint at the direction of the motion.
The answer is the distance moved * the component of your 14 lbs in the direction of the motion.