SIMPLE AND COMPOUND MACHINE
DURING A RESCUE OPERATION, FIREFIGHTERS NEED TO SPLIT OPEN A JAMMED DOOR QUICKLY. WHICH SIMPLE MACHINE WOULD BE MOST EFFECTIVE FOR THIS TASK?
WEDGE
A CONSTRUCTION COMPANY TESTS TWO CRANES. CRANE A USES 600 N OF INPUT FORCE TO LIFT A 2,400-N LOAD. THE ENGINEER WANTS TO DETERMINE HOW MANY TIMES THE MACHINE MULTIPLIES THE APPLIED FORCE TO COMPARE ITS PERFORMANCE WITH OTHER CRANES. DETERMINE THE ACTUAL MECHANICAL ADVANTAGE.
4
MOTOR OIL FLOWS MUCH MORE SLOWLY THAN WATER WHEN POURED AT ROOM TEMPERATURE. WHICH PROPERTY OF FLUIDS BEST EXPLAINS THIS OBSERVATION?
VISCOSITY
A RESEARCH SUBMARINE IS TESTING A NEW FLOATATION DEVICE. DURING THE EXPERIMENT, THE DEVICE DISPLACES 0.040 M³ OF WATER. USING A WATER DENSITY OF 1,000 KG/M³ AND G = 9.8 M/S², DETERMINE THE BUOYANT FORCE ACTING ON THE DEVICE.
392 N
A HYDRAULIC LIFT IS DESIGNED TO RAISE SMALL VEHICLES USING AN INPUT FORCE OF 200 N APPLIED TO A 0.020-M² PISTON. THE OUTPUT PISTON HAS AN AREA OF 0.50 M². DETERMINE THE OUTPUT FORCE PRODUCED BY THE LIFT.
5,000 N
A BICYCLE COMBINES A WHEEL AND AXLE, LEVERS, GEARS, AND OTHER SIMPLE MACHINES TO HELP A RIDER TRAVEL EFFICIENTLY. HOW SHOULD THIS MACHINE BE CLASSIFIED?
COMPOUND MACHINE
TO MAKE A WHEELCHAIR RAMP EASIER TO USE, AN ARCHITECT DESIGNS A RAMP THAT IS 8 M LONG TO REACH A PLATFORM 2 M HIGH. DETERMINE THE IDEAL MECHANICAL ADVANTAGE OF THE RAMP.
4
AFTER A LIGHT RAIN, SMALL WATER DROPLETS REMAIN BEADED ON THE SURFACE OF A CAR INSTEAD OF SPREADING OUT. WHICH PROPERTY OF FLUIDS CAUSES THIS BEHAVIOR?
SURFACE TENSION
A DIVER OBSERVES THAT A SUBMERGED OBJECT EXPERIENCES A BUOYANT FORCE OF 490 N WHILE COMPLETELY UNDERWATER. USING THE DENSITY OF WATER, DETERMINE THE VOLUME OF WATER DISPLACED BY THE OBJECT.
0.050 M³
A HYDRAULIC PRESS MUST GENERATE AN OUTPUT FORCE OF 12,000 N TO SHAPE METAL. IF THE OUTPUT PISTON AREA IS 0.60 M² AND THE INPUT PISTON AREA IS 0.03 M², DETERMINE THE REQUIRED INPUT FORCE.
600 N
A WORKER MUST LIFT BUILDING MATERIALS TO THE ROOF WHILE STANDING ON THE GROUND. WHICH SIMPLE MACHINE ALLOWS HIM TO PULL DOWNWARD INSTEAD OF LIFTING UPWARD DIRECTLY?
FIXED PULLEY
A FACTORY MACHINE RECEIVES 800 J OF INPUT WORK, BUT ONLY 640 J IS CONVERTED INTO USEFUL OUTPUT WORK DUE TO FRICTION AND HEAT LOSS. DETERMINE THE EFFICIENCY OF THE MACHINE.
80%
DURING AN OIL SPILL, THE OIL REMAINS ON THE SURFACE OF THE OCEAN INSTEAD OF MIXING WITH THE WATER. WHICH PROPERTY OF FLUIDS MOST DIRECTLY EXPLAINS THIS?
DENSITY
A SCIENCE TEAM TESTS AN UNKNOWN LIQUID. AN OBJECT DISPLACES 0.020 M³ OF THE LIQUID AND EXPERIENCES A BUOYANT FORCE OF 196 N. DETERMINE THE DENSITY OF THE UNKNOWN LIQUID.
1,000 KG/M³
A HYDRAULIC MACHINE USES A 0.040-M² INPUT PISTON WITH AN INPUT FORCE OF 400 N TO PRODUCE AN OUTPUT FORCE OF 8,000 N. DETERMINE THE REQUIRED AREA OF THE OUTPUT PISTON.
0.80 M²
TWO MECHANICS TIGHTEN THE SAME SCREW. ONE USES A SCREWDRIVER WITH A LARGER HANDLE AND FINDS THE JOB EASIER BECAUSE OF THE MACHINE BUILT INTO THE TOOL. WHICH SIMPLE MACHINE IS RESPONSIBLE?
WHEEL AND AXLE
A MACHINE HAS AN ACTUAL MECHANICAL ADVANTAGE OF 5. IF IT LIFTS A 3,000-N LOAD, DETERMINE THE INPUT FORCE NEEDED TO OPERATE THE MACHINE.
600 N
A LARGE STEEL SHIP IS ABLE TO FLOAT EVEN THOUGH STEEL IS DENSER THAN WATER. WHICH PROPERTY OF FLUIDS PROVIDES THE UPWARD FORCE THAT SUPPORTS THE SHIP?
BUOYANCY
AN INDUSTRIAL MACHINE OPERATES IN OIL WITH A DENSITY OF 800 KG/M³. ONE OF ITS COMPONENTS DISPLACES 0.050 M³ OF OIL. DETERMINE THE BUOYANT FORCE ACTING ON THE COMPONENT.
392 N
A HYDRAULIC SYSTEM PRODUCES AN OUTPUT FORCE OF 6,000 N USING AN OUTPUT PISTON AREA OF 0.30 M². IF THE INPUT FORCE IS 300 N, DETERMINE THE AREA OF THE INPUT PISTON.
0.015 M²
A MOVING COMPANY MUST LOAD A 400-KG SAFE INTO A TRUCK WITHOUT USING A CRANE. THEY DECIDE TO INCREASE THE DISTANCE OVER WHICH THE FORCE IS APPLIED TO REDUCE THE EFFORT REQUIRED. WHICH SIMPLE MACHINE SHOULD THEY USE?
INCLINED PLANE
AN ENGINEER IMPROVES A MACHINE SO THAT IT OPERATES AT 90% EFFICIENCY. IF THE MACHINE RECEIVES 2,000 J OF INPUT WORK, DETERMINE THE AMOUNT OF USEFUL OUTPUT WORK PRODUCED.
1,800 J
MAPLE SYRUP POURS MUCH MORE SLOWLY THAN WATER FROM THE SAME CONTAINER. WHICH PROPERTY OF THE SYRUP IS GREATER?
VISCOSITY
ENGINEERS TEST A FLOATING PLATFORM THAT EXPERIENCES A BUOYANT FORCE OF 980 N IN FRESHWATER. DETERMINE THE VOLUME OF WATER DISPLACED BY THE PLATFORM.
0.100 M³
A CAR'S HYDRAULIC BRAKE SYSTEM USES AN INPUT FORCE OF 150 N APPLIED TO A PISTON WITH AN AREA OF 0.015 M². THE OUTPUT PISTON HAS AN AREA OF 0.45 M². DETERMINE THE OUTPUT FORCE THAT ACTS ON THE BRAKE PAD.
4,500 N