1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kogti [31]
3 years ago
11

Can someone please help me with this physics question? I'm desperate!

Physics
1 answer:
Lelu [443]3 years ago
3 0

Answer:

a) 2·√10 seconds

b) Linda should be approximately 30.6 meters

c) Jenny's speed at the 100-m mark is approximately 6.325 m/s

Explanation:

The speed with which Linda is running = 8.6 m/s

The point Jenny starts = The 80-m mark

The acceleration of Jenny = 1.0 m/s²

a) The time it takes Jenny to run from the 80-m mark to the 100-m mark, <em>t</em>, is given as follows

Δs = u·t + (1/2)·a·t²

Δs = Distance = 100-m - 80-m = 20-m

u = The initial velocity of Jenny = 0

a = Jenny's acceleration = 1.0 m/s²

∴ 20 = 0×t + (1/2) × 1 × t² = t²/2

20 = t²/2

t = √(20 × 2) = 2·√10

The time it takes Jenny to run from the 80-m mark to the 100-m mark = 2·√10 seconds

b) The distance Linda runs in t = 2·√10 seconds, d = v × t

Given that Linda's velocity, v = 8.6 m/s, we have;

d = 8.0 × 2·√10 = 16·√10

The distance Linda runs in t = 2·√10 seconds = 16·√10 meters ≈ 50.6 meters

Therefore, Linda should be approximately (50.6 - 20) meters = 30.6 meters behind Jenny when Jenny starts running

c) Jenny's speed at the 100 m mark is given as follows;

v = u + a·t

t = 2·√10 seconds, a = 1.0 m/s², u = 0

∴ v = 0×t + 1.0×2·√10 = 2·√10 ≈ 6.325

Jenny's speed at the 100-m mark ≈ 6.325 m/s

You might be interested in
PLEASE HELP THIS IS DUE TODAY!! (GIVING BRAINLIEST TO WHOEVERY ANSWERS QUICKLY AND CORRECTLY!) 15 POINTS!
Jlenok [28]

As the core collapses, the outer layers of the star are expelled. A planetary nebula is formed by the outer layers. The core remains as a white dwarf and eventually cools to become a black dwarf. ... Like low-mass stars, high-mass stars are born in nebulae and evolve and live in the Main Sequence

hydrogen shell burning - outer layers swell. Red Giant Branch - helium ash core compresses - increased hydrogen shell burning. First Dredge Up - expanding atmosphere cools star - stirs carbon, nitrogen and oxygen upward - star heats up.

5 0
3 years ago
A wave of infrared light has a speed of 6 m/s and a wavelength of 12 m. What is the frequency of this wave?
givi [52]
I'll be happy to solve the problem using the information that
you gave in the question, but I have to tell you that this wave
is not infrared light.

If it was a wave of infrared, then its speed would be close
to 300,000,000 m/s, not 6 m/s, and its wavelength would be
less than 0.001 meter, not 12 meters.

For the wave you described . . .

             Frequency  =  (speed)  /  (wavelength)

                                 =  (6 m/s)  /  (12 m)

                                 =      0.5 / sec

                                 =      0.5 Hz .  

(If it were an infrared wave, then its frequency would be
greater than 300,000,000,000 Hz.)
5 0
3 years ago
Read 2 more answers
How is social media changing the world as we know it?
Vika [28.1K]

Answer:

Social media has helped many businesses grow and promote itself, and has helped people find a better way to connect and communicate with one another. On the other hand, it's also provided many people with problems involving mental health, emotional insecurities, and waste of time

Explanation:

what they said is correct

4 0
2 years ago
Help
Blizzard [7]
We can approach this in another way.
We know that sin(∅) = height / hypotenuse.

Thus, for x, height is 1 and hypotenuse is 3. Using Pythagoras theorem,
3² = 1² + b²
b = √8
cos(x) = b/hypotenuse
cos(x) = √8 / 3

Now, lets consider y:
sec(y) = 1 / cos(y) = 1 / base / hypotenuse = hypotenuse / base
The hypotenuse is 25 and the base is 24. We again apply Pythagoras theorem to find the third side, which works out to be:
height = 7
sin(y) = height / hypotenuse
sin(y) = 7/25

Now, sin(x + y) =
sin(x)cos(y) + sin(y)cos(x)
= (1/3)(24/25) + (√8 / 3)(7/25)
= 8/25 + 7√8/75
= (24 + 14√2) / 75
6 0
3 years ago
Read 2 more answers
As water rises through the troposphere and cools, it changes from a(n) ————- to a(n) ———— through the process of condensation; w
Hoochie [10]

Answer:

GAS,   LIQUID,    CLOUDS

Explanation:

Water can be in three states: solid, liquid and gas, passing from one to another depending on the pressure and temperature.

In this complementation exercise.

When the water cools down the GAS goes to the LIQUID state, these small drops unite and form the CLOUDS

4 0
3 years ago
Other questions:
  • Where does the autotroph get its energy from
    9·1 answer
  • Why should you explore the potential roadblocks to your chosen career?
    13·1 answer
  • How long would this acceleration last
    6·1 answer
  • What are the similarities in the 3 types of waves
    6·1 answer
  • A projectile is fired with an initial speed of 100 m/s and angle of elevation 30 degrees. The projectile eventually hits the gro
    9·1 answer
  • Pink
    7·1 answer
  • Describe five things that you do to make yourself feel warmer or cooler.
    15·1 answer
  • When three people with a total mass of 2.00 x 102 kg step into their 1.200 x 103 kg car, the car’s
    12·1 answer
  • All about Henry Mosléy?<br>​
    8·1 answer
  • 17. How long will it take for an object accelerating at a constant rate of 5 m/s to change its velocity from 0 to 6 m/s? (A) 0.6
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!