Step-by-step explanation:
A is the correct answer of this question
vi is going in the positive direction (up). (That's my choice). a (acceleration) is going in the minus direction (down). The directions could be reversed.
Givens
vi = 160 ft/s
vf = 0 (the rocket stops at the maximum height.)
a = - 9.81 m/s
t = ????
Remark
YOu have 4 parameters between the givens and what you want to solve. Only 1 equation will relate those 4. Always always list your givens with these problems so you can pick the right equation.
Equation
a = (vf - vi)/t
Solve
- 32 = (0 - 160)/t Multiply both sides by t
-32 * t = - 160 Divide by -32
t = - 160/-32
t = 5
You will also need to solve for the height to answer part B
t = 5
vi = 160 m/s
a = - 32
d = ???
d = vi*t + 1/2 a t^2
d = 160*5 + 1/2 * - 32 * 5^2
d = 800 - 400
d = 400 feet
Part B
You are at the maximum height. vi is 0 this time because you are starting to descend.
vi = 0
a = 32 m/s^2
d = 400 feet
t = ??
formula
d = vi*t + 1/2 a t^2
400 = 0 + 1/2 * 32 * t^2
400 = 16 * t^2
400/16 = t^2
t^2 = 25
t = 5 sec
The free fall takes the same amount of time to come down as it did to go up. Sort of an amazing result.
Answer:
firstly you know the term of multiplication
like 5*2=10 ,10*2=20, 20*2 =40 and 40*2 =80
and last three numbers are 80, 160,320
The number of hours spent playing video games is the independent variable and cumulative grade point average is the dependent variable.
<h3>What is an independent variable?</h3>
An independent variable simply means the variable that's changed to test the effect on the dependent variable.
Here, the number of hours spent playing video games is the independent variable and cumulative grade point average is the dependent variable.
This is because the number of hours is being used to predict cumulative grade point average.
Learn more about variables on:
brainly.com/question/25223322
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