Aball is projected upward at time t = 0.0 s from a point on a roof 90 m above the ground. the ball rises, then falls and strikes the ground. the initial velocity of the ball is 80.5 m/s. the velocity of the ball when it is 89 m above the ground is about : im making this short and simple .

The velocity of the ball when it is 89 meters above the ground is about: E. - 81 m/s

Given the following data:

To find velocity of the ball when it is 89 m above the ground, we would use the third equation of motion;

Mathematically, the third equation of motion is given by the formula:

Velocity, V = 80.62 ≈ 81 m/s

But since the ball is falling, the velocity would be negative.

Velocity, V =  - 81 m/s

Therefore, the velocity of the ball when it is 89 meters above the ground is about - 81 m/s.

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Option D.

Step-by-step explanation:

A ball is projected upward with an initial velocity = 80.5 m per second.

Height of the roof from the ground is 90 m.

Equation that represents the relation between velocity and height when thrown upwards is

Here final velocity v = 0, initial velocity u = 80.5 meter per second and g = 9.8 m per second²

0 = (80.5)² - 2(9.8)h

19.6h = 6480.25

h = meters

Total height of the ball from the ground = 90 + 330.625 = 420.625 m

Now we have to calculate the velocity of the ball at the height = 89 m

Distance covered by the ball falling freely form the point above 420.625

Distance covered by the ball above 89 m = 420.625 - 89 = 331.625 m

We plug in the values in the formula

v² = u² + 2gh

v² = 0 + 2(9.8)(331.625)

v = √6499.85 = 80.62 m

  ≈ 81 m

And the sign notation will be negative

Therefore option D. (-81 m) is the answer.

the number of the people going.

step-by-step explanation:

the cost to buy one movie ticket is $7. if the total cost for the movie is a function of how many people go, then the input is : the number of the people going.

answer: solve 5\cdot 2^x=2405⋅2  

x

=2405, dot, 2, start superscript, x, end superscript, equals, 240.

solution

to solve for xxx, we must first isolate the exponential part. to do this, divide both sides by 555 as shown below. we do not multiply the 555 and the 222 as this goes against the order of operations!

\begin{aligned} 5\cdot 2^x& =240 2^x& =48 \\ \end{aligned}  

5⋅2  

x

2  

x

​    

=240

=48

​

step-by-step explanation: