Answer:
B. 2 meters.
Explanation:
To rotate the capstan a certain amount of torque is required, and if each sailor applies a force 
at a distance 
from the center, then for two sailors the total torque will be
;
therefore, for one sailor to apply the same torque it must be that the torque 
he applies must be equal to the torque that the two sailors applied:
which gives
.
and since 
,
which is choice B.
Answer:
B. Axial stress divided by axial strain
Explanation:
Elasticity:
It is the tendency of an object to deform along the axis when an opposing force is applied without facing permanent change in shape.
Plasticity:
When an object crosses the elasticity limit, it enters plasticity where the change due to stress is permanent and the object might even break.
Yield strength:
Yield strength is the point of maximum bearable stress that indicates the limit of elasticity.
Our case:
As the stress applied is less than the yield strength, the rod is still in the elasticity state and its modulus can be calculated.
Modulus of Elasticity = Stress along axis/Ratio of change in length to original length
Axial strain is basically the ratio of change in length to original length.
So, Modulus of Elasticity = Axial Stress/ Axial Strain
The spring starts out 22 cm long with nothing hanging on it.
Hanging 35 newtons of weight on it stretches the spring 1 meter.
Ellen is going to hang 250 grams of mass on the spring.
What's the weight of 250 grams of mass ?
Weight = (mass) x (acceleration of gravity in the place where the mass is) .
On Earth, the acceleration of gravity is 9.8 m/s² .
250 grams is 0.25 of a kilogram.
Weight of 250 grams = (0.25 kilogram) x (9.8 m/s²)
= (0.25 x 9.8) kg-m/s²
= 2.45 newtons .
2.45 newtons of weight is (2.45 / 35) of 35 newtons,
so it'll stretch the spring (2.45 / 35) of a meter.
2.45/35 = 0.07 of a meter = 7 centimeters.
The spring was 22 cm long with nothing hanging on it,
and the 250-gm weight stretched it 7 cm.
So with the weight hanging on it, it's (22 + 7) = 29 cm long.
Answer:
<em>Thermal energy</em>
Explanation:
<u>Electrical Energy
</u>
The electrical energy has been found to be an excellent resource to power our modern lifestyle. It can be produced in several ways including hydroelectrical plants, thermal plants, nuclear plants, solar panels, among many others. Each one of them converts different types of energy into electrical energy.
When converting to electrical energy, some equipment is needed, like generators, transformers, cables, circuit breakers, and every kind of devices with specific functions to have a good and safe electrical service. Each device has an internal resistance that opposes the flow of current. The resistances produce thermal energy as a result of current flowing through them. It's not possible to avoid this waste of energy, electrical engineers do their best to use better materials and configurations to reduce the thermal waste to a minimum.
Answer:
A. 
B. 
Explanation:
The frequency has an inversely proportional relationship with the concept of wavelength, the greater the wavelength, the lower the frequency. For electromagnetic waves, the frequency is equal to the speed of light, divided by the wavelength.
A.
B.
