Answer:
Some work input is lost to friction
Explanation:
The efficiency of a machine is defined as:
(1)
where
is the work output
is the work input
Due to the law of conservation of energy, the work output can never be larger than the work input (because energy cannot be created). Moreover, in real machines part of the work input is lost due to the presence of frictions: as a result, part of the energy in input is converted into thermal energy or other forms of energy, and so the work output is smaller than the work input, and so the ratio (1) becomes less than 1, and so the efficiency is less than 100%.
Answer:
Explanation:
The buoyant force F is equal to the weight of the displaced fluid. The weight of the displaced fluid is 
, where 
is the mass of the displaced fluid. The mass of the displaced fluid is 
, where 
is the density of the fluid and 
is the displaced volume, which is equal to the submerged volume of the cilinder 
.
Putting all together we have:
Answer:
Answer:
4, 2, 5, 3, 1
Explanation:
The neuron remains at RMP unless stimulated. The stimulus results in opening of stimulus channels, this causes depolarization. if the extent of depolarization reaches to the level of threshold, the sodium and potassium channels begin opening but potassium channels are slow to open. Hence at first sodium goes out causing further depolarization until it reaches the peak at which the potassium channels open and the sodium channels close. This causes the potassium to rush our causing repolarization i.e. return of the membrane potential to RMP but the potassium channels are slow to close and it leads to hyperpolarization (undershoot) making the membrane potential more negative due to excessive movement of potassium outside the cell. Once the potassium channels close, the leak channels and Na K pump acts to return the potential to RMP.
Explanation:
Answer:
See explanation
Explanation:
The centripetal force keeps an object moving in a circular orbit at constant velocity. The velocity of an object undergoing uniform motion is always tangential to the circle while the centripetal force is directed towards the center of the circle.
This now implies that the direction of the force acting on a body undergoing circular motion at constant velocity is perpendicular to the direction in which the object is being displaced.
