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Two forces F1 and F2 acting on the same object, on the same line, their resultant force is 20n. It is known that F2 = 50N, and the direction of F2 is the same as that of resultant force
If the direction of F2 is the same as that of resultant force, then F1 = f2-20n = 30n;
If the direction of F2 is opposite to the direction of resultant force, then F1 = F2 + 20n = 70N
As shown in the figure, the force of the trolley used by the person standing on the car is F1, and the static friction force behind the car is F2
Number of visits: 524 reward points: 5 | solution time: June 26, 2010 17:48 | questioner: zxcvbnml1234
A when the car moves at a constant speed, the total work done by F1 and F2 is 0
B when the car accelerates, the total work done by F1 and F2 is positive
C when the car accelerates, the total work done by F1 and F2 is negative
D no matter what kind of motion the car does, the total work done by F1 and F2 is 0
The total work of F1 and F2 is 0
B when the car accelerates, the total work done by F1 and F2 is positive
C when the car accelerates, the total work done by F1 and F2 is negative
D no matter what kind of motion the car does, the total work done by F1 and F2 is 0
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