An astronaut on the planet Zircon tosses a rock horizontally with a speed of 7.15 m/s. The rock falls through a vertical distance of 1.40 m and lands a horizontal distance of 8.95 m from the astronaut. What is the size of the acceleration due to gravity on Zircon

Yvette hangs a 2.4kg bird feeder in the middle of a rope tied between two trees. the feeder creates a tension of 480 n in each side of the the rope.

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)

Explain why electric current cannot exist if a current doesn't have a voltage source.