1. A 12m window hanging scaffolding basket supporting an80Kg man and paint material? The scaffolding is hanging by a steelrope at eacch end. The basket weight is 40 Kg, the paint is 25Kglocated at the middle. The man is located at themiddle.

1. Draw the forces diagram.

2. What are the forces F1 and F2 at the ropes holding thebasket at the ends?

b) The man moves 4 meters towards F2, will F1 & F2change?    

c) Find the new F1 & F2 forces exerted on thescaffolding in b above. ∑Ƭ cw=∑Ƭccw & Ƭ=Fd?

         

1. Two cars of equal weights of (1400lb each) were subjectto an inelastic head-on collision. One car was traveling eastboundat 50mi/h speed and the other car was traveling westbound at 60mi/hspeed.   

1. What was the direction of the motion after collision?        

2. What was the speed after collision? m1V1+m2V2=(m1+ m2)V’;  

3. How far they went after 1.4 seconds? convert V to ft/s;S=(V)’.(t)

1. Two men exert 115 lb force each to push a car fordistance of 150 feet.

1. What is the Work done in lb ft?W=F.S   

2. What is the power exerted after 5 minutes?P=W/t  

3. If the road is at an angle of 15o uphill. What is themechanical advantage of the road?

4. What is the force of the effort required to move the1000lb car the 150 ft in c above?

  

1. A submersible gasoline pump was used to lift 210gallons/min of gasoline from the bottom of a tank 20 ft belowground level. (One gallon gasoline is 6.3 lb)

1. What is the power rating of the submersible pump? P=W/t=F.S/t    

2. How many gallons can be lifted in 10minutes?   

1. A 1000 lb box was moved using inclined plane (h=5ft andL=20ft: MA=L/h), a wheel and axle simple machine (wheel diameter is2 ft and the axle is 0.5 ft: MA=D/d) and 3 pulleys with 3 movablesstrands.

1. Find the Mechanical Advantage of the inclined plane andthe wheel and axle

2. Find the MA of the system (MA = MA1 x MA2 xMA3)

3. Find the exerted effort.

1. True or False questions.

	Question	T/F
a	Angular velocity is measured in RPM or radians perseconds Â
b	Using 3 gears connected directly, we obtain oppositedirection of rotation
c	Friction free machine does not exist commercially and itis costly to make
d	One Horsepower UOM and equal to 550 lb ft/s
e	A wheelbarrow is 2 simple machines named the lever andthe wheel & axle.
f	Forces are at equilibrium if the sum of their x & ycomponents are Zeros
g	To convert mi/hr to ft/s; we multiply by5280
h	To Convert Km/hr to m/s; we multiply by(1000/3600)
i	Impulse = the product of the object mass & change invelocity
j	When the Kinetic Energy and Potential energy are equalin a roller coaster, the height of the car will be: h = ½(Constant/m.g) , Constant=PE+KE