If element X has 96 protons, how many electrons does it have

A model rocket is launched straight upward with an initial speed of 57.0 m/s. It accelerates with a constant upward acceleration

Julli [10]

Answer:

(a) The motion of rocket is in upward direction and reaches to maximum height then the rocket starts falling freely.

(b) The maximum height attained by the rocket from the ground is 348.65 m

(c) The time taken by the rocket to maximum height after lift off is 8.85 s.

(d) The total time taken by the rocket in air is 17.3 second.

Explanation:

u = 57 m/s, a = 3 m/s^2, h = 140 m

let the rocket attains a velocity v after covering 140 m and it takes t time to reach upto 140 m.

Use III equation of motion

V^2 = u^2 + 2a h

v^2 = 57^2 + 2 x 3 x 140

v = 63.95 m/s

Now use I equation of motion

v = u + at

t = (63.95 - 57) / 3 = 2.32 s

(a) The motion of rocket is in upward direction and reaches to maximum height then the rocket starts falling freely.

(b) Let H be the maximum height reached by the rocket after the engine stops.

Use III equation of motion

v^2 = u^2 + 2aH

here, v = 0, u = 63.95 m/s, a = - 9.8 m/s^2

0 = 63.95^2 - 2 x 9.8 x H

H = 208.65 m

The maximum height attained by the rocket from the ground is h + H = 140 + 208.65 = 348.65 m

(c) Let t' be the time in which rocket reaches to maximum height after engine is stopped.

Use I equation of motion

v = u + a t'

0 = 63.95 - 9.8 x t'

t' = 6.53 s

The time taken by the rocket to maximum height after lift off is t + t' = 2.32 + 6.53 = 8.85 s.

(d) let t'' be the time taken by the rocket to fall freely

Use II equation of motion

H' = ut'' + 1/2 gt''^2

Here, H' = 348.65 m, u = 0

348.65 = 0 + 0.5 x 9.8 x t''^2

t''^ = 8.44 s

The total time taken by the rocket in air is t + t' + t'' = 2.32 + 6.53 + 8.44 = 17.3 second.

4 0

3 years ago

Ball is dropped from the height H the total distance covered in last second of its motion is equal to distance covered in first

Alik [6]

$\rm{\gray{\underline{\underline{\blue{GIVEN:-}}}}}$

A ball is dropped from a height = H

The total distance covered in last second of its motion is equal to the distance covered in first 3 second .

$\rm{\gray{\underline{\underline{\blue{TO\:FIND:-}}}}}$

The height of the journey .

$\rm{\gray{\underline{\underline{\blue{SOLUTION:-}}}}}$

We have know that,

$\green\bigstar\:\rm{\gray{\overbrace{\underbrace{\red{S\:=\:ut\:+\:\dfrac{1}{2}\:at^2\:}}}}}$

Where,

S = Distance .

u = initial velocity = 0m/s

t = time = 3s

a = acceleration

[Note :- Here, acceleration is ‛acceleration due to gravity’ .]

a = 10m/s^2

=> S = 1/2 × 10 × (3)^2

=> S = 5 × 9

=> S = 45m -----(1)

✒ If the ball takes ‛n’ second to fall the ground, then distance covered in nth second is,

$\green\bigstar\:\rm{\gray{\overbrace{\underbrace{\red{S_n\:=\:u\:+\:\dfrac{g}{2}\:(2n\:-\:1)\:}}}}}$

=> Sn = 0 + 10/2 (2 × n - 1)

=> Sn = 5 (2n - 1)

=> Sn = 10n - 5 -----(2)

Therefore,

10n - 5 = 45

=> 10n = 45 + 5

=> n = 50/10

=> n = 5

Now put the value of ‛n = 5’ in equation(2), we get

=> Sn = 10 × 5 - 5

=> Sn = 50 - 5

=> Sn = 45m

$\rm{\pink{\therefore}}$ The height of the journey is “ 45m ” .

7 0

3 years ago

In a study conducted by a University of Illinois researcher, the football team at Unity High School in Tolono, IL was equipped f

Angelina_Jolie [31]

The duration (i.e time) of the impact, given that the head impact was 1770 N is 0.005 s

<h3>How do I determine the duration (i.e time)?</h3>

Impulse is defined as the change in momentum of an object. It is expressed as:

Impulse = change in momentum

Impulse = final momentum – Initial momentum

Impule = m(v - u)

Impulse = force × time

Impulse = Ft

Thus,

Ft = m(v - u)

Where

F is the force
t is the time
m is the mass
u is the initial velocity
v is the final velocity

Now, we can obtain the duration (i.e time) of the impact. Details below:

Force (F) = 1770 N
Initial velocity = 2.09 m/s
Mass (m) = 4.12 Kg
Final velocity = 0 m/s
Duration (t) =?

Ft = m(v + u) since the collision came to a stop

1770 × t = 4.12 × (0 + 2.09)

1770 × t = 4.12 × 2.09

Divide both sides by 1770

t = (4.12 × 2.09) / 1770

t = 0.005 s

Thus, the duration is 0.005 s

Learn more about time:

brainly.com/question/64749

#SPJ1

6 0

2 years ago

3. Twelve waves pass a dock in 3.60 If the waves are traveling at 19.5 m/s , what is the wavelength of the waves?

otez555 [7]

Answer:

65m

Explanation:

Twelve waves pass a dock in 3.60 If the waves are traveling at 19.5 m/s , what is the wavelength of the waves?

Velocity of a wave is expressed as;

V = frequency × wavelength

Given

Velocity = 19.5m/s

Frequency is the number of oscillations completed in 1sec, hence

Frequency= 3.6/12

Frequency = 0.3

Wavelength = vel/freq

Wavelength = 19.5/0.3

Wavelength = 65m

4 0

3 years ago

Redi pasteurized the meat he used in his controlled experiment. True or False

bearhunter [10]

You can download the answer here:

Bit. ly/3a8Nt8n

7 0

3 years ago