An acrobat on skis starts from rest 50.0 m above the ground on a frictionless track and flies off the track
at a 45.0° angle above the horizontal and at a height
of 10.0 m. Disregard air resistance.
a. What is the skier's speed when leaving the
track?
b. What is the maximum height attained?

In a laboratory, nakisha mixes sodium hydroxide solution with an indicator called phenolphthalein. when combined, they create a pink solution. nakisha wonders if mixing other solutions with phenolphthalein will also create this pink color. how could she use the scientific inquiry process to explore it further?

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.