Arock is thrown upward from the level ground in such a way that the maximum height of its flight is equal to its horizontal range r.
(a) at what angle θ is the rock thrown? °
(b) in terms of its original range r, what is the range rmax the rock can attain if it is launched at the same speed but at the optimal angle for maximum range? rmax =
(c) would your answer to part (a) be different if the rock is thrown with the same speed on a different planet? yes no

Act has a 1200: 5 or 240: 1 turns ratio. it is short circuited. what is the maximum current at 1200a primary if we put a 100ohm resistor across the secondary end of the ct. use it as current source circuit.

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.

Select the best definition for wavelength. the height of an oscillating electromagnetic wave the rate at which electromagnetic waves oscillate. the distance between two crests of an electromagnetic wave. the oscillations of electric and magnetic fields select the best definition for frequency. the oscillations of electric and magnetic fields. the height of an oscillating electromagnetic wave. the distance between two crests of an electromagnetic wave. the rate at which electromagnetic waves oscillate