A sphere of mass 0.5kg is dropped into a column of oil. At the instant the sphere becomes completely submerged in the oil, the sphere is moving downward at 8m/s , the buoyancy force on the sphere is 4.0N , and the fluid frictional force is 4.0N . Which of the following describes the motion of the sphere at this instant

sphere moves with a constant terminal velocity.

Explanation:

mass of sphere, m = 0.5 kg

velocity downward, v = 8 m/s

buoyant force = 4 N

fluid friction force = 4 N

Weight of the sphere is acting downward.

W = mg = 0.5 x 10 = 5 N

When the object is immersed in a fluid and it moves in the fluid with constant velocity, it means the net force acting on the object is zero, and the object attains a terminal velocity.

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.

in physics zero. in muscle fatigue could be high