Answer:
Work done on an object is equal to
FDcos(angle).
So, naturally, if you lift a book from the floor on top of the table you do work on it since you are applying a force through a distance.
However, I often see the example of carrying a book through a horizontal distance is not work. The reasoning given is this: The force you apply is in the vertical distance, countering gravity and thus not in the direction of motion.
But surely you must be applying a force (and thus work) in the horizontal direction as the book would stop due to air friction if not for your fingers?
Is applying a force through a distance only work if causes an acceleration? That wouldn't make sense in my mind. If you are dragging a sled through snow, you are still doing work on it, since the force is in the direction of motion. This goes even if velocity is constant due to friction.
Explanation:
Answer:
w=3.05 rad/s or 29.88rpm
Explanation:
k = coefficient of friction = 0.3900
R = radius of the cylinder = 2.7m
V = linear speed of rotation of the cylinder
w = angular speed = V/R or to rewrite V = w*R
N = normal force to cylinder
N=


These must be balanced (the net force on the people will be 0) so set them equal to each other.





There are 2*pi radians in 1 revolution so:

So you need about 30 RPM to keep people from falling out the bottom
Answer:
Yes
Explanation:
If the acceleration has an opposite direction to the velocity of the car, this means that it is opposed to is motion. Therefore, it is called deceleration, since the car's velocity will decrease until it stops and then will start it moving towards the west.
Answer:
True b and c
Explanation:
In an RLC circuit the impedance is
![Z = \sqrt{[R^{2} + ( (wL)^{2} + (\frac{1}{wC})^{2} ] }](https://tex.z-dn.net/?f=Z%20%3D%20%5Csqrt%7B%5BR%5E%7B2%7D%20%2B%20%28%20%28wL%29%5E%7B2%7D%20%2B%20%28%5Cfrac%7B1%7D%7BwC%7D%29%5E%7B2%7D%20%5D%20%20%20%20%20%7D)
examine the different phrases..
a) False. The maximum impedance is the value of the resistance
b) True. Resonance occurs when
(wL)² + (1 / wC)² = 0
w² = 1 / LC
c) True. In resonance the impedance is the resistive part and the power is maximum
d) False. In resonance the inductive and capacitive part cancel each other out
e) False. The impedance is always greater outside of resonance, but at the resonance point they are equal
Answer:
they differ each other bc it is a lot of with earth quakes and everything.
Explanation: