Two point charges of 9μC and 4μC are placed a distance of 4 m apart. a. Calculate the magnitude of the force, in Newtons, on a positive 5μC charge at the midpoint between the two charges.

b. Find the point, measured in meters from the 9μC charge, between the two charges where the force on the 5μC charge is 0?

Abaseball is thrown a distance of 20 meters. what is its speed if it takes 0.5 seconds to cover the distance

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.

Apatient has a history of poor nutrition. he has skin rashes, bleeding gums, and a cut that hasn’t healed in a long time. what vitamin deficiency most likely caused this symptom?