Chapter 11, Problem 3RP

F දි = m A gardening company is testing a wheelbarrow prototype for seniors. The wheel has a hub motor which can apply a moment M = 29 N·m. If the wheel has a radius r = 0.2 m and the wheel rolls without slipping, determine the power of the hub motor if it moves at a constant velocity of v= 1.5 when a force of F = 15 N is applied at an angle of 0 = 30°. Determine the efficiency of the motor if a total of 375 W is put into it. S Power generated by the motor ONLY Pmotor 237 0 (input as decimal) M x W

2-43. Determine, and show on a sketch of the co- ordinate system, the resultant of each of the parallel, noncoplanar force systems that satisfies the following conditions: (a) Σ F, = 40 lb ↑ , Σ M. = 100 ft-lb and Σ M₁ = 160 ft-lb; (b) Σ F, = 50 lb ↓, Σ M₁ = 150 ft-lb and ; Σ Μ. = 90 ft-lb di (c) Σ F, = 20 1b \ , Σ M, = 60 1-10 λ s. Σ Μ, = 40 ft-b and

the three showed forces are equivalent to one ascending force of 50kN in A and has a torque of 170kN*m in couter-clockwise sense. Determine P and Q

3-45. The lug nut on the wheel of the automobile is to be removed using the wrench and applying the vertical force of F = 30 Nat A. Determine if this force is adequate, provided 14 N- m of torque about the x axis is initially required to turn the nut. If the 30-N force can be applied at A in any other direction, will it be possible to turn the nut? F = 30 N 0.25 m 03my 0.5 m 0.1 my

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solve by the concepts of statics on a paper with proper method

3/15 Find the angle of tilt e with the horizontal so that the contact force at B will be one-half that at A for the smooth cylinder. 45 45

The control lever is subjected to a clockwise couple of 112 N-m exerted by its shaft at A and is designed to operate with a 300-N pull as shown. If the resultant of the couple and the force passes through A, determine the proper dimension x of the lever. Assume F = 300 N, a = 145 mm, 0 = 24° Answer: x = i mm t A

The device shown is a part of an automobile seat-back-release mechanism. The part is subjected to the 4.1-N force exerted at A and a 250-N-mm restoring moment exerted by a hidden torsional spring. Determine the y-intercept of the line of action of the single equivalent force. Your answer will be positive if the intercept is above O and negative if below O. F = 4.1 N 18 mm 16° 31 mm 250 N-mm Answer: y = mm