Information Technology      Technology of THAT About Problems of mechanisms

1º In the handle of the image is wanted to raise a weight of R-value. To calculate this value considering that the maximum effort that can do the finger is of 10 kg Solution: 5 kg 2º In the following handles, reasons if the handle is turned to the right, to the left or is in balance Solution: a) Left, b) balance c) right, d) left, e) right and f) left 3 º the crane is designed to raise a load of 5000 Nw. If one goes of a certain length, marked as? , to let the opportune calculations to know if we run the risk of which one falls. Solution: 10 meters 4º the wheelbarrow of the image responds to a handle of the type to _________________.Calcular the fully factored load if the worker can make a maximum force of 500 Nw. Solution: 1250 Nw 5º Calcular the force that there is to apply in the end of the cord for each one of the blocks and tackle and in the handles that there are underneath the blocks and tackle. Solution:100 Nw and 1000 Nw  . In the handles 200 Nw and 3600 Nw 6 º In the following system of gears, the wheel marked with shoots with an arrow yellow tour to 100 r.p.m. To calculate for each case, the direction of rotation of each and the speed of turn Data:  Wheel pequeña-> 10 teeth. Wheel median - > 30 teeth. Great wheel - > 60 teeth. Pulley - > 10cm and 4 pulley 5 - > 40 cm. Solution: a) Left to 33.3 rpm b) Right, left with wheel 3 turning to 16.66 rpm c) Right, left with turn from 3 to 50 rpm d) Left to 16.66 rpm e) 8.33 rpm 7º a motor tour to 500 r.p.m and is united to a gear of 20 teeth. The small wheel moves another great one of 100 teeth by means of a metallic chain. To calculate the speed at which the great wheel (b) moves. Solution: 100 r.p.m 8º a pinion has 10 teeth and 200 tour rpm. To calculate the speed of the rack if in each cm are 5 teeth. Solution. 400 cm/minuto 9. In the figure of the washing machine, it is appraised that the motor moves by means of the strap, to the drum of the washing machine. If the diameters of the pulleys are 7 and 40 cm, to calculate the speed of the drum if the motor 4000 tour to r.p.m. Solution: 700 r.p.m  10º In the following figure, the small gears have 10 teeth and the wheels great 40, To that speed will turn the last gear, if the motor gear does at a speed of 200 rpm. Solution: 12,5 r.p.m 11º the bicycle has a plate with 40 teeth that the pinion of 10 moves. If the cyclist pedals 50 times in a minute and the wheels have a radius of 30 cm, to calculate:  Angular velocity of the wheel  Linear rate of the bike Solution: 5.652 km /h

To spend a time to him to solve it. If you are not able, you have the exercise solved in the part inferior of this page. 12º Indica the names that of the most important elements of the steam engine  13º Complete the names of turbofan   14º In the image is a detail of a cylinder.  That it names it corresponds to each number of the indicated ones in the same and what time of the 4 is? 15º Next is three times in a gasoline motor. It reasons in what time is each.

Resolution of the exercise of the bicycle:

1º Tenemos a system of chain with plate of 40 teeth that moves a pinion of 10 and therefore, the speed of the pinion (that is of the back wheel) is: Speed of plate X plate teeth = Speed of pinion X teeth pinion 50 xs 40 = V X 10   => Speed of pinion = 2000/10 = 200 rpm.

2º Now we have wheel turns it to 200 rpm. A return of the wheel advances so much as the length of the perimeter and as the perimeter comes dice by 2 Xs π X R = 2 xs 3.14 xs 30 cm = 188.4 cm = 1.884 meters. This for a return, for 50 we have 1.884 xs 50 = 94.2 ms