Compare the mass on Neptune (68.11) to the weight on Neptune (905.863). What is the difference? Why is there a difference?

A swimmer bounces straight up from a diving board and falls feet first into a pool. She starts with a velocity of 3.00 m/s, and

Leya [2.2K]

Answer:

A) 0.9844 s

B) x2 = 0.4587 m

C) v = 6.657 m/s

Explanation:

We are given;

Height of take off point above pool; x1 = 1.8 m

Initial take off velocity; u = 3 m/s

Final velocity at highest point before free fall; v = 0 m/s

B) To find the highest point above the board her feet reaches means the distance from take off to the top of the motion just before free fall.

Thus, we will be using equation of motion and we have;

v² = u² + 2gs

Now, let s = x2 which will be the distance between take off and the top before free fall.

So;

v² = u² + 2g(x2)

Now,since the motion is against gravity, g will be negative.

Thus;

v² = u² + 2(-9.81)(x2)

Plugging in the relevant values to give;

0² = 3² - (19.62x2)

19.62(x2) = 9

x2 = 9/19.62

x2 = 0.4587 m

A) We want to find how long her feet is in air.. It means we want to find out the time to get to a distance of x1 and also the time to achieve the distance (x1 + x2) on free-fall.

Thus, using equation of motion;

v = u + gt

Again, g = -9.81

Thus;

0 = 3 - 9.81t1

9.81t1 = 3

t1 = 3/9.81

t1 = 0.3058 s

Now, for the time taken to achieve the distance (x1 + x2) on free-fall, we will use the formula;

s = ut + ½gt²

Where s = (x1 + x2) = 1.8 + 0.4587 = 2.2587 m

And now, u = 0 m/s because the start of the free fall is from maximum height with velocity of 0 m/s. Again, g = - 9.81 m/s²

Thus;

2.2587 = 0 - ½(-9.81)(t2)²

2.2587 = 4.905(t2)²

(t2)² = 2.2587/4.905

(t2)² = 0.4605

t2 = √0.4605

t2 = 0.6786 s

Thus, total time of feet in air = t1 + t2 = 0.3058 + 0.6786 = 0.9844 s

C) Velocity when feet hit the water would be given by;

v = u + gt

Where u = 0 m/s and t = t2 = 0.6786

Since it's in direction of gravity, g = 9.81 m/s

v = 0 + (0.6786 × 9.81)

v = 6.657 m/s

4 0

3 years ago

For a projectile launched horizontally, which of the following best describes the downward component of a projectile's velocity?

Angelina_Jolie [31]

C. The downward component of the projectile's velocity continually increases

Explanation:

The motion of a projectile consists of two independent motions:

- A uniform motion (with constant velocity) along the horizontal direction

- A uniformly accelerated motion, with constant acceleration (equal to the acceleration of gravity) in the downward direction

Here we want to study the downward component of the projectile's velocity. Since the vertical motion is a uniformly accelerated motion, the vertical velocity is given by:

$v=u+at$

where

u = 0 is the initial vertical velocity (zero since the projectile is fired horizontally)

$a=g=9.8 m/s^2$ downward is the acceleration of gravity

t is the time

So the equation becomes

$v=gt$

This means that

C. The downward component of the projectile's velocity continually increases

Because every second, it increases by $9.8 m/s$ in the downward direction.

Learn more about projectile motion:

brainly.com/question/8751410

#LearnwithBrainly

8 0

3 years ago

4. How long will it take a car travelling with a speed of 160 km hr to cover a distance of 700 meters? Hint: km/hr should be con

Inessa [10]

Answer:

15.8 seconds

Explanation:

Create an extended calculation to convert all the unit to what you need.

160 km 1000 m 1 hour 1 min

----------- x ------------- x -------------- x ---------- = 44.4 m/s

1 hour 1 km 60 min 60 sec

So 160km/hr is equal to 44.4m/s

Now you can figure out how many seconds it will take to go 700 meters.

44.4 m

---------- X x sec = 700 m

1 sec

Solve for x sec

x sec = 700m / 44.4 m/s

= 15.8 seconds

3 0

3 years ago

Anyone know what type of circuit this is?

Oksana_A [137]

Answer:

C

Explanation:

BECAUSE ITS GOING ON AND ON IF ITS NOT CORRECT I WILL VOTE YOU BRAINLEST ON MY QUESTION

3 0

2 years ago

QUICKKK I NEEEED HELP PLZ!!!!!!!!!!!!

avanturin [10]

There would be martial law (just elaborate on the definition) and the population would go awry(elaborate on subject)

4 0

3 years ago