How to solve kinematics problems involving constant velocity and acceleration?

AI Thread Summary
To solve kinematics problems involving constant velocity and acceleration, it's essential to apply the appropriate equations of motion. For the first problem, use the equations for free fall and constant velocity to determine the lake's depth. In the second problem, set up equations for the cart's motion and Jill's acceleration to find the distance the cart travels before being caught. The third problem requires analyzing the rocket's motion and the bolt's fall to calculate the rocket's acceleration. Understanding how to integrate these concepts is key to solving the kinematics problems effectively.
julianne
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Kinematics Homework Help!

There are a few of my homework Problems I am having trouble with:
1) A lead ball is dropped into a lake from a diving board 5.80 above the water. After entering the water, it sinks to the bottom with a constant velocity equal to the velocity with which it hit the water. The ball reaches the bottom 3.50 after it is released. How deep is the lake?


2)Jill has just gotten out of her car in the grocery store parking lot. The parking lot is on a hill and is tilted . Fifty meters downhill from Jill, a little old lady let's go of a fully loaded shopping cart. The cart, with frictionless wheels, starts to roll straight downhill. Jill immediately starts to sprint after the cart with her top acceleration of 2 m/s^2 . How far has the cart rolled before Jill catches it?

3)A rocket is launched straight up with constant acceleration. Four seconds after liftoff, a bolt falls off the side of the rocket. The bolt hits the ground 7.10 later. What was the rocket's acceleration?


In all of the problems I have the basic understanding of the equations and knowledge needed to solve them but am having some trouble putting it all together. Thanks!

Julianne
 
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how do you think these problems should be solved? any guesses?
 
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