A body of weight w is attached by a string of length L, to a hook on a vertical wall.  A horizontal force F acting on the body holds it at a distance d from the wall.  Derive the equation, which gives the force F in terms of w, L, and d.

A box is hanging from two strings. String #1 pulls up and left, making an angle of 50⁰ with the horizontal on the left, and string #2 pulls up and to the right with a force of 110 N, making an angle of 65° with the horizontal on the right. Find the mass of the box. Hint: Apply EFx = 0 and ΣFy = 0 Your Answer: Answer

A particle, which remains at rest, is acted on by three forces R, S and T. The force R has magnitude 32 N and is directed vertically downwards. The force S is directed to the left and up at 55◦ to the horizontal. The force T is directed to the right and up at 42◦ to the horizontal. Take the unit vector i to point horizontally to the right and the unit vector j to point vertically upwards as attached. Express the forces in component form, in terms of unknown magnitudes where appropriate. Find the magnitude of S in newtons to two significant figures.

You are out on a hike and come across an unfortunate scene: a fellow hiker has fallen off a ledge. You happen to be carrying a long rope, and bravely decide to help. You tie the rope to a rock of mass mR=500 kgmR=500 kg and make your way over the ledge (see figure). If the coefficient of static friction between the rock and the ground is μS=0.355μS=0.355, and your mass is mH=70.5 kgmH=70.5 kg, what is the maximum mass of the fallen hiker (mFmF) that the rock can hold so that you two can make it back up from the ledge? Assume that where the rope passes the ledge is frictionless and that the rope is parallel to the ground.

Force T pulls at angle a up from the horizontal on a section of pipe of weight W as shown, but the pipe remains motionless. The coefficient of static friction between pipe and floor is µ. We know that the magnitude of the total frictional force on the pipe by the floor is: 1(c T. A) 27 cos a B) µ(W +T sin a) C) µW +T cos a D) T cosa W A B

A 2.5 kg block is initially at rest on a horizontal surface. A horizontal force F of magnitude 6.2 N and a vertical force P are then applied to the block. The coefficients of friction for the block and surface are ls = 0.37 and Uk = 0.22. (a) Determine the magnitude of the frictional force acting on the block if the magnitude of P is 8. N. (b) Determine the magnitude of the frictional force acting on the block if the magnitude of P is 10.0 N. N (c) Determine the magnitude of the frictional force acting on the block if the magnitude of P is 12.0 N. N Submit Answer

A block with mass m₁ = 9.5 kg rests on the surface of a horizontal table which has a coefficient of kinetic friction of uk = 0.67. A second block with a mass m₂ = 9.1 kg is connected to the first by an ideal string passing over an ideal pulley such that the second block is suspended vertically. The second block is released from rest, and motion occurs. Write an expression using the variables provided for the magnitude of the tension force, T. m₁ Ti y -X

For the next three items: A 200 kg plank is projecting a distance L = 5.0 m from a wall which is held steadily by a string that is connected to it at an angle = 30° from the horizontal. The plank is actually fasted to the wall where an unknown force F is exerted on the plank by the wall. If a 60 kg mass is placed on the plank at a distance d = 1.0 m, find the tension force on the string. Ө d O 1300 N O 4200 N O 1600 N O2200 N L-

A 250 gram block on a 30 deg inclined plane is attached by an inextensible string going over a frictionless pulley to a 500 gram hanging weight. The static and kinetic friction coefficients are .25 and .123. While moving, what is the tension ii the connecting string? O 174530 dynes O 121000 dynes O 262400 dynes O 7430 dynes O 42930 dynes

A particle, which remains at rest, is acted on by three forces F, G and H. The force F has magnitude 55 N and is directed to the left and up making an angle of 45 degrees with the vertical The force G is directed vertically down and H is directed to the right and up making an angle of 60 degrees with the vertical. Find the magnitude of the vectors G and H, giving your answers to one decimal place. The magnitude of G is N (to 1 d.p.) The magnitude of H is N (to 1 d.p.)