Answer:
I think the answer is A. X: Mold Y: Cast
Explanation:
Hope that helps!!!
Answer:
For elliptical orbits: seldom
For circular orbits: always
Explanation:
We start by analzying a circular orbit.
For an object moving in circular orbit, the direction of the acceleration (centripetal acceleration) is always perpendicular to the direction of motion of the object.
Since acceleration has the same direction of the force (according to Newton's second law of motion), this means that the direction of the force (the centripetal force) is always perpendicular to the velocity of the object.
So for a circular orbit,
the direction of the velocity of the satellite is always perpendicular to the net force acting upon the satellite.
Now we analyze an elliptical orbit.
An elliptical orbit correponds to a circular orbit "stretched". This means that there are only 4 points along the orbit in which the acceleration (and therefore, the net force) is perpendicular to the direction of motion (and so, to the velocity) of the satellite. These points are the 4 points corresponding to the intersections between the axes of the ellipse and the orbit itself.
Therefore, for an elliptical orbit,
the direction of the velocity of the satellite is seldom perpendicular to the net force acting upon the satellite.
Answer:
72.04 dB.
Explanation:
The intensity level of 60dB corresponds to the sound intensity 
given by the equation
where 
solving for we get:
Now, when 16 violins are playing the intensity becomes
which on the decibel scale gives
.
Thus, playing 16 violins together gives the intensity level of 72 dB.
It will be traveling at 11m/s, because there is no friction in empty space.
