Which of the following is not a benefit of improved cardio-respiratory fitness?

A body with initial velocity 8.0 m/s moves along a straight line with constant acceleration and travels

Aleksandr [31]

Answer:

(a) The average velocity is 16 m/s

(b) The acceleration is 0.4 m/s^2

(c) The final velocity is 24 m/s

Explanation:

Constant Acceleration Motion

It's a type of motion in which the velocity (or the speed) of an object changes by an equal amount in every equal period of time.

Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, final speed is calculated as follows:

$v_f=v_o+at\qquad\qquad [1]$

The distance traveled by the object is given by:

$\displaystyle x=v_o.t+\frac{a.t^2}{2}\qquad\qquad [2]$

(a) The average velocity is defined as the total distance traveled divided by the time taken to travel that distance.

We know the distance is x=640 m and the time taken t= 40 s, thus:

$\displaystyle \bar v=\frac{x}{t}=\frac{640}{40}=16$

The average velocity is 16 m/s

Using the equation [1] we can solve for a:

$\displaystyle a=\frac{v_f-v_o}{t}$

(c) From [2] we can solve for a:

$\displaystyle a= 2\frac{x-v_ot}{t^2}$

Since vo=8 m/s, x=640 m, t=40 s:

$\displaystyle a= 2\frac{640-8\cdot 40}{40^2}=0.4$

The acceleration is 0.4 m/s^2

(b) The final velocity is calculated by [1]:

$v_f=8+0.4\cdot 40$

$v_f=8+16=24$

The final velocity is 24 m/s

3 0

2 years ago

The curved section of a horizontal highway is a circular unbanked arc of radius 740 m. If the coefficient of static friction bet

kirill [66]

The answer would be 54 m/s as the maximum speed

8 0

3 years ago

Water is called the “universal solvent.” Which statement best explains this description with respect to ionic compounds?

Semmy [17]

I think it is c for the answer

6 0

2 years ago

A lamp marked 100w 250v is lit up for 10hours, costs 2I what is the cost of lighting the lamp

olga nikolaevna [1]

Answer:

2k

Explanation:

100W X 10h = 1000Wh = 1KWh thus cost is 2k

3 0

1 year ago

HELP PLZ

Stells [14]

Answer:

Explanation:

Use the equation

$h(t)=-16t^2+v_0t+h_0$

where h(t) is the height after a certain amount of time goes by, v0t is the initial upwards velocity, and h0 is the initial height of the projectile. For us:

h(t) = 10

v0t = 80

h0 = 3 and filling in:

$10=-16t^2+80t+3$ and get everything on one side to factor:

$0=-16t^2+80t-7$

This factors to

t = .09 sec and 4.9 sec. Let's interpret this.

The time of .09 is when the ball reached 10 feet on the way up, and

the time of 4.9 is when the ball reached 10 feet on the way back down. That's the height we need, 4.9 seconds.

5 0

2 years ago