Answer:
Power_input = 85.71 [W]
Explanation:
To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.
where:
W = work [J] (units of Joules)
F = force [N] (units of Newton)
d = distance [m]
We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.
Now replacing:
![W = (80*10)*3\\W = 2400 [J]](https://tex.z-dn.net/?f=W%20%3D%20%2880%2A10%29%2A3%5C%5CW%20%3D%202400%20%5BJ%5D)
Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.
where:
P = power [W] (units of watts)
W = work [J]
t = time = 40 [s]
![P = 2400/40\\P = 60 [W]](https://tex.z-dn.net/?f=P%20%3D%202400%2F40%5C%5CP%20%3D%2060%20%5BW%5D)
The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.
![Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W]](https://tex.z-dn.net/?f=Effic%3D0.7%5C%5CEffic%3DP_%7Brequired%7D%2FP_%7Bintroduced%7D%5C%5CP_%7Bintroduced%7D%3D60%2F0.7%5C%5CP_%7Bintroduced%7D%3D85.71%5BW%5D)
<span>In most cases, magma differentiation (a.k.a. fractional crystallization produces magma with higher silica content than the parent magma. Fractional crystallization removes early formed minerals in magma. The liquid that does not react to the process remains in the magma. </span>
Answer:
.
Explanation:
By Newton's Second Law, the acceleration 
of an object is proportional to the net force 
on it. In particular, if the mass of the object is 
, then
.
Rewrite this equation to obtain:
.
In this case, the assumption is that the 
force is the only force that is acting on the object. Hence, the net force on the object would also be
Make sure that all values are in their standard units. Forces should be in Newtons (same as 
, and the acceleration of the object should be in meters-per-second-squared (
). Apply the equation to find the mass of the object.
.
A book falls to the floor.
A car skids to a stop.
A foam ball launches from a spring (Are the right answer, just did this one 4:34 pm Jan/21/19)
