Help please!!! the question and answer choices are on the pic!

If a ball is thrown straight up into the air with an initial velocity of 70 ft/s, its height in feet after t seconds is given by

Vitek1552 [10]

Answer:

a) Average velocity at 0.1 s is 696 ft/s.

b) Average velocity at 0.01 s is 7536 ft/s.

c) Average velocity at 0.001 s is 75936 ft/s.

Step-by-step explanation:

Given : If a ball is thrown straight up into the air with an initial velocity of 70 ft/s, its height in feet after t seconds is given by $y = 70t-16t^2$ .

To find : The average velocity for the time period beginning when t = 2 and lasting. a. 0.1 s. , b. 0.01 s. , c. 0.001 s.

Solution :

a) The average velocity for the time period beginning when t = 2 and lasting 0.1 s.

$(\text{Average velocity})_{0.1\ s}=\frac{\text{Change in height}}{0.1}$

$(\text{Average velocity})_{0.1\ s}=\frac{h_{2.1}-h_2}{0.1}$

$(\text{Average velocity})_{0.1\ s}=\frac{(70(2.1)-16(2.1)^2)-(70(0.1)-16(0.1)^2)}{0.1}$

$(\text{Average velocity})_{0.1\ s}=\frac{69.6}{0.1}$

$(\text{Average velocity})_{0.1\ s}=696\ ft/s$

b) The average velocity for the time period beginning when t = 2 and lasting 0.01 s.

$(\text{Average velocity})_{0.01\ s}=\frac{\text{Change in height}}{0.01}$

$(\text{Average velocity})_{0.01\ s}=\frac{h_{2.01}-h_2}{0.01}$

$(\text{Average velocity})_{0.01\ s}=\frac{(70(2.01)-16(2.01)^2)-(70(0.01)-16(0.01)^2)}{0.01}$

$(\text{Average velocity})_{0.01\ s}=\frac{75.36}{0.01}$

$(\text{Average velocity})_{0.01\ s}=7536\ ft/s$

c) The average velocity for the time period beginning when t = 2 and lasting 0.001 s.

$(\text{Average velocity})_{0.001\ s}=\frac{\text{Change in height}}{0.001}$

$(\text{Average velocity})_{0.001\ s}=\frac{h_{2.001}-h_2}{0.001}$

$(\text{Average velocity})_{0.001\ s}=\frac{(70(2.001)-16(2.001)^2)-(70(0.001)-16(0.001)^2)}{0.001}$

$(\text{Average velocity})_{0.001\ s}=\frac{75.936}{0.001}$

$(\text{Average velocity})_{0.001\ s}=75936\ ft/s$

5 0

3 years ago

|5x|-2=18 helps love this problem please help

drek231 [11]

Answer:

x = 4

Step-by-step explanation:

The absolute value of 5x is still 5x.

5x - 2 = 18

Add 2 to both sides

5x = 20

Divide both sides by 5

x = 4

7 0

3 years ago

Read 2 more answers

John works two jobs as a security guard he earns $9.75 per hour as a landscaper he earns $14 per hour one week john worked a tot

Yuliya22 [10]

Answer:

He worked 26 hours as a security guard and 4 hours as a landscaper

Step-by-step explanation:

7 0

3 years ago

The solution to 4x + 7 - 9 = -14 is a0.

Alchen [17]

Answer:

Isolate the variable by dividing each side by factors that don't contain the variable.

x = − 3

Step-by-step explanation:

4 0

3 years ago

Help me with this immediately

BARSIC [14]

Answer:

complementary angles, x=19

Step-by-step explanation:

since the two parts of the angle add up to 90, they are complementary angles.

you can find x by adding them and setting it equal to 90:

3x-2+2x-3 = 90

5x-5 = 90

5x = 95

x = 19

5 0

3 years ago