If you assume in advance that the block will not move, then the equations you wrote down are correct. But they are not written down in a convenient coordinate system. Let's work with your equations first.

The assumption that the block will not move can be incorrect. However, this is not a problem, because you can use your equations to solve for both the normal force N and the friction force f. The value for f you get must then be interpreted as the friction force that is necessary for the block to remain at rest. You then calculate the ratio of f and N to see if it exceeds us. If not, then the block will indeed remain at rest. If the ratio exceeds us, then the block will accelerate. The friction force of f you ...

Solution Summary

The friction force acting on a block is determined. A free-body diagram is provided for the question.

... there are two independent forces acting on two different blocks. On block P there is the force of the spring, while on block B its the friction force, and both ...

...force of 6 Newtons acts in the direction of motion of a block of mass 9 Kg, with the mass being pulled across the floor against a frictional force of .6 Newtons ...

... frame of the lower block, two horizontal forces are acting... the two blocks increases, the pseudo force fP also ... The forward frictional drag f2 on the upper block...

... All the forces acting on the system are shown in ...Frictional force acts backwards (opposite to the direction of motion ... Normal reaction N = weight of block A = 25 ...

... However, the magnitude of limiting friction is 1.4 times the kinetic friction. ... is acted on by only (a) a single nonzero force, (b) two forces that point in ...

... where Ff ' is the frictional force due to the block, N ' is the normal force acting on the base ... Now the last three forces cancel since they all act in the ...

... horizontal motion of the lower block, the forces acting on it are force applied F ... T of the string in backward direction and the friction force on lower and ...

... up", in the direction of the lift force on the ... These two problems on friction and banking angle of ... In the figure, all the forces acting on the concrete blocks...

... The forces acting on the block of mass m2= 4.0 kg ... down the incline, weight of the block m2g vertically ... the tabletop N and the kinetic friction force F = k N ...