Why is free-fall referred to as uniform acceleration? If we consider an object in free-fall to be accelerating uniformly, what effects are we neglecting?

I know that velocity can be zero when the accleration is not.  An example is when a ball is thrown in the air, and that instant moment before it begins to drop, the velocity is zero.  What would acceleration equal?  Would it equal gravity (9.8m/s^2)?If so, how would I prove that?

A helicopter blade spins at exactly 115 revolutions per minute. Its tip is 6.50 m from the center of rotation. (a) Calculate the average speed (in m/s) of the blade tip in the helicopter's frame of reference. m/s (b) What is its average velocity (in m/s) over one revolution? m/s

Suppose that in the future humans can travel to different earth like planets within our galaxy. You take a trip to a new planet with a different gravitational acceleration than earth. To test this gravitational acceleration, you decide to drop a ball a distance of 2 meters. You measure how long it takes the ball to fall 2.0 meter multiple times and take an average. The average drop time is 0.52 seconds. What is the approximate magnitude of the gravitational acceleration of the planet (in units of m/s squared)?

How would  I begin to solve this problem? In Example 2.6, we considered a simple model for a rocket launched from the surface of the Earth. A better expression for a rocket's position measured from the center of the Earth is given by y(t) = (RE3/2 + 3*(g/2)1/2 REt)2/3 where RE is the radius of the Earth (6.38 ✕ 106 m) and g is the constant acceleration of an object in free fall near the Earth's surface (9.81 m/s2). (a) Derive expressions for vy(t) and ay(t). (Use the following as necessary: g, RE, and t. Do not substitute numerical values; use variables only.)

You have put a sonar device at the top of a frictionless inclined plane, as shown in the diagram below. That device allows you to measure the distance an object is from the device, as well as the speed and the acceleration of that object. If we decide that the origin (h = 0) is at the sonar device, we want to know what the height change is as we slide down the incline. 0 For an angle below the horizontal of 6.46, we see that our object has slid a distance 1.13 m, as measured along the incline itself. Calculate the height change in meters - and report your answer as a negative number. (This value would be useful for calculating the change in gravitational potential energy, as we will do in the lab.) h=o 10% O i 26 QUATU 99+ hp X 55 83°F 3:11 PM 10/16/2022 Ctrl 0

A newly constructed spaceship has a length of 100.0 m (as measured in the rest frame). This spaceship departs the Earth, bound for a distant planet located a distance D = 50.0 light-years away from the Earth. It travels at a constant speed of v = 0.900c.   Part A) As measured by Mission Control on Earth, how long does the journey take? Enter the numerical value in units of years. Part B) According to an astronaut on the spaceship, how long does the journey take? Enter the numerical value in units of years. Part C) As measured by Mission Control on Earth, what is the spaceship's apparent length? Enter the numerical value in SI units

The gravitational force on mars is a little more than one-third of that on earth. If a basketball player were to jump vertically with the same initial velocity on Mars as she does on Earth, then the amount of time taken to reach maximum height would be what? 3 times less OR 3 times more?