# Answer the questions. "DO NOT SEND THE SIMILAR QUEIRIES" Q.E8. A boy pulls a toy car with a force of 50 N through a strng which makes an angle of 30 with the horizontal, so as to move the toy by a distance of 1 m in the horizontal direction. If the string were inclined at an angle of 45 with the horizontal, how much pull would he apply along the string in order to move it through the same distance of 1 m?

Hi Khushboo, I have sent another answer too
Here it is. This is about the conditions for no work done

Hi Khushboo, recall W = F * s * cos @
So the two possibilities are :
When no displacement is made  by force F i.e s = 0 , then work W =0
When the force is perpendicular to the displacement then cos 90 =0
Now new question:
Force is 50 N
Angle of inclination with horizontal 30. So component of force along horizontal = 50 * cos 30 = 50./3/2 = 25./3 N
Displacement in the direction of this force = 1 m
Hence work performed = 25./3 J
Now in new situation angle of inclination = 45
Hence if F is the required force then component along horizontal = F cos 45 = F/./2 N
Displacement = 1 m
So work performed = F/./2 J
As F/./2 = 25./3
We have F = 25./6 N

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