Answer:
work output is always less than work input - the ratio is less than 1.
Explanation:
This principle comes from the fact that a machine or system cannot produce more work than is supplied to it, because this would violate the energy conservation law (work is a type of mechanical energy).
In theoretical machines called "ideal machines" the input work is the same as the output work, but these machines are only theoretical because in real applications there is always some type of energy loss, either in heat produced by a machine or processes for its operation, for this reason the output work is always less than the input work.
Regarding the ratio work output to work input:

because work input WI is always greater than work output WO.
Answer:
ρ = 7500 kg/m³
Explanation:
Given that
mass ,m = 12 kg
Displace volume ,V= 1.6 L
We know that
1000 m ³ = 1 L
Therefore V= 0.0016 m ³
When metal piece is fully submerged
We know that
mass = Density x volume

Now by putting the values in the above equation

ρ = 7500 kg/m³
Therefore the density of the metal piece will be 7500 kg/m³.
Answer:
skateboard b
Explanation:
p=mv
skateboard a
p=(60kg)(1.5m/s)=90kg*m/s
skateboard b
p=(50kg)(2m/s)=100kg*m/s
Answer: Wavelength is related to light and also related to energy. The shorter the wavelengths and the higher the frequency corresponds with greater energy. So the longer the wavelengths and lower the frequency results in lower energy. The energy equation is E = hν.
Explanation:
It is given that,
Voltage of the battery, V = 12 V
Current, I = 100 ampere-hours
Energy stored is given by the product of power and time taken. So,

P is the power, 

P = 1200 watts
This power can be used for 1 hour or 3600 seconds
Energy, 
E = 4320000 J
So, the energy stored in this battery is 4320000 J. Hence, this is the required solution.