Final answer:
The mechanical advantage (MA) of a wheel and axle is calculated by dividing the radius of the wheel by the radius of the axle. In this case, the radius of the axle is 7 cm and the MA can be calculated as 100 cm / 7 cm = 14.3. The velocity ratio (VR) and efficiency cannot be determined without additional information.
Step-by-step explanation:
The mechanical advantage (MA) of a wheel and axle is calculated by dividing the radius of the wheel by the radius of the axle. In this case, the radius of the axle is 7 cm and the MA can be calculated as follows:
MA = Radius of Wheel / Radius of Axle
MA = 100 cm / 7 cm = 14.3
The MA of the wheel and axle is 14.3.
The velocity ratio (VR) is the ratio of the distance moved by the effort to the distance moved by the load. In this case, the VR can be calculated as follows:
VR = Distance Moved by Effort / Distance Moved by Load
Since the problem does not specify the distances moved by the effort and load, the VR cannot be determined without additional information.
The efficiency of a machine is calculated by dividing the useful work output by the work input, and then multiplying by 100% to express the result as a percentage. In this case, the efficiency can be calculated as follows:
Efficiency = (Useful Work Output / Work Input) x 100%
Since the problem does not provide information about the work output and work input, the efficiency cannot be determined without additional information.