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:
d, e
Step-by-step explanation:
The applicable rules of exponents are ...
(a^b)(a^c) = a^(b+c)
a^-b = 1/a^b
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In this case, it means the product is ...
(6^1)(6^0)(6^-3) = 6^(1+0-3) = 6^-2 = 1/6^2 = 1/36
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The 6 without an exponent is equivalent to 6^1, an exponent of 1.
The sum of the exponents is -2.
Add the exponents to simplify the expression.
The value of the expression is 1/36.
An equivalent is any expression that results in 6^-2. One such is (6^5)(6^-7).
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Only the last two choices, d and e, apply.
100% because
is 6 and
is 9 meaning that the sum will come up at 6 or 9 also meaning that its 100%
Answer:
c
Step-by-step explanation:
Step 1: calculate the number
everytime the number goes up by 5 so we can assume that it will be 25
step 2: find the letter
it just goes by the alphabet so we can assume it will be e.
the letter always follows the number and it alternates between uppercase and lower case and last time it was uppercase so it will be lowercase.
Therefore it will be 25e
