Answer:
approximately 30 degrees
Explanation:
If it takes the cannonball 2 seconds to reach the maximum height, we can use the analysis of the vertical component of the velocity and the fact that the acceleration of gravity is the one acting opposite to this initial vertical component 
of the velocity. We know as well that at the top of the trajectory, the vertical component of the velocity is zero, and then the movement starts going down in it trajectory. So, the final velocity for the first part of the ascending movement is zero, giving us the following equation for the velocity under an accelerated movement (with acceleration of gravity "g" acting):
By knowing the vertical component of the initial velocity (19.6 m/s), and the actual magnitude of the total initial velocity (40 m/s), we can calculate what angle was the initial velocity vector forming above the horizontal. We use for such the fact that the sine of the angle relates the opposite side of a right angle triangle with the hypotenuse, and solve for the angle using the arcsin function:
which tells us that the closer answer shown is 
Explanation:
It is given that,
Distance between wires, d = 3.5 mm = 0.0035 m
Power of light bulb, P = 100 W
Potential difference, V = 120 V
(a) We need to find the force per unit length each wire of the cord exert on the other. It is given by :
Power, P = V × I
This gives, 
(b) Since, the two wires carry equal currents in opposite directions. So, teh force is repulsive.
(c) This force is negligible.
Hence, this is the required solution.
Answer:
B
Explanation:
The correct answer is B) have unlike charges. Since they are attracted to each other they have to be unlike
Two terminal device which can maintain a fixed voltage. Hope this help I need more detail in your question this is all I can provide. :)
