Find the work done by a force of 200 pounds acting in the direction -i + 2j in moving an object 75 feet from (0,0) to (-75,0).
A) 13,416.1 ft-lb
B)6708.2 ft-lb
C) 15,000.0 ft-lb
D) 8944.9 ft-lb

Question

Find the work done by a force of 200 pounds acting in the direction -i + 2j in moving an object 75 feet from (0,0) to (-75,0).
A) 13,416.1 ft-lb 
B)6708.2 ft-lb 
C) 15,000.0 ft-lb 
D) 8944.9 ft-lb

anonymous · Answer

I know how to do the majority of this problem, but the thing i am not sure of is what direction $$-i+2j$$ is

anonymous · Answer

$$W=||F||*||AB||*\cos \theta$$

anonymous · Answer

so...
$$W = 200 * 75*\cos \theta$$
I am lacking the ability/knowledge to convert $$-i+2j$$ into an angle

amistre64 · Answer

break it into its component parts

the force triangle is similar to the vectors triangle

amistre64 · Answer

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