MECHANISMS

THE WORKING WAY OF THIS SIMPLE MACHINE IS BASED ON

• WHEELS

• PULLEYS

• LEVERS

• CRANKS

WE WANT TO MOVE A STONE OF 300KG WEIGHT, WHAT EFFORT SHOULD YOU MAKE TO LIFT IT IN EACH OF THE PULLEY SYSTEMS?

• 100, 200, 300

• 200,400, 600

• 300, 150, 100

• 300, 200, 100

THE IMAGE ABOVE IS A:

• DOUBLE PULLEY MECHANISM
• WORM GEAR MECHANISM
• FRICTION DRIVES MECHANISM
• GEARS MECHANISM

IN A BIKE THERE IS A MECHANISM CALLED

• GEARS WITH A CHAIN
• GEARS WITH PINION
• PULLEYS WITH CHAIN
• GEARS WITH BELT

1ST CLAS , 2ND CLASS AND 3RD CLASS LEVERS ARE:

• PLIERS, WHEELBARROW AND FISHING ROD
• SCISSORS, PLIERS AND SEESAW
• PULLEYS, HAMMER AND NUT CRACKLE
• ALL OF THEM

WHAT CLASS ARE ALL THE  LEVERS IN THE PICTURE? 

• 1ST
• 2ND
• 3RD
• 1ST AND 2ND

What is the STRONGER pulley in this mechanism?

• The drive pulley

• The driven pulley

• They have the same strenght

• They can´t move

IN THIS PULLEYS SYSTEM, BIG PULLEYS ARE DOUBLE SIZE THAN SMALL ONES. HOW MANY TIMES THE SPEED WILL BE MODIFIED IN THE LAST ONE (PURPLE)?

• IT WILL BE REDUCED 4 TIMES

• IT WILL BE INCREASED 4 TIMES

• IT WILL BE REDUCED TWICE

• IT WILL BE INCREASED TWICE

What effort (F) is needed to lift the stone (R=50 kg ) with this lever?

(force arm=2m ; resistance arm= 1m)

• 50 kg

• 25 kg

• 100 kg

• 75 kg

If red gear rotates clockwise, what will the rotation sense be for the rest of the gears?

• Blue and green clockwise

• Yellow and blue anticlockwise

• Yellow and green anticlockwise

• None of them are true