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:
Solution :
********************************************
Two angles are said to be a pair of
adjacent angles if they have a common
arm and lie on the either sides of the
common arm .
***********************************************
Now ,
i ) a , b are a pair of adjecent angles .
ii ) c , d are pair of adjecent angles.
iii ) e, f are not adjecent angles .
Step-by-step explanation:
Answer:
40 = d+q
7.15=0.10d+0.25q
there are 19 dimes and 21 quarters.
B I think but i could be totally wrong
Answer:
Hence after 3.98 sec i.e 4 sec Object will hit the ground .
Step-by-step explanation:
Given:
Height= 6 feet
Angle =28 degrees.
V=133 ft/sec
To Find:
Time in seconds after which it will hit the ground?
Solution:
<em>This problem is related to projectile motion for objec</em>t
First calculate the Range for object and it is given by ,
(2Ф)/
Here R= range g= acceleration due to gravity =9.8 m/sec^2
1m =3.2 feet
So 9.8 m, equals to 9.8 *3.2=31.36 ft
So g=31.36 ft/sec^2. and 2Ф=2(28)=56
fts
Now using Formula for time and range as
Vx is horizontal velocity
Ф
(28)
ft/sec
So above equation becomes as ,
T is approximately equals to 4 sec.
