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
Andre45 [30]
3 years ago
13

PLZ HELP ON #22-26!!!! Please explain why and how you got your answer.

Physics
1 answer:
AleksAgata [21]3 years ago
5 0
22. a - (vf^2 - vi^2)/(2d) 
a = (0 - 23^2)/(170) 
a = -3.1 m/s^2

23. Find the time (t) to reach 33 m/s at 3 m/s^2
33-0/t = 3 
33 = 3t 
t = 11 sec to reach 33 m/s^2
Find the av velocuty: 33+0/2 = 16.5 m/s
Dist = 16.5 * 11 = 181.5 meters to each 33m/s speed. Runway has to be at least this long. 

24. The sprinter starts from rest. The average acceleration is found from: 
(Vf)^2 = (Vi)^2 = 2as ---> a = (Vf)^2 - (Vi)^2/2s = (11.5m/s)^2-0/2(15.0m) = 4.408m/s^2 estimated: 4.41m/s^2
The elapsed time is found by solving
Vf = Vi + at ----> t = vf-vi/a = 11.5m/s-0/4.408m/s^2 = 2.61s

25. Acceleration of car = v-u/t = 0ms^-1-21.0ms^-1/6.00s = -3.50ms^-2
S = v^2 - u^2/2a = (0ms^-1)^2-(21.0ms^-1)^2/2*-3.50ms^-2 = 63.0m 

26. Assuming a constant deceleration of 7.00 m/s^2
final velocity, v = 0m/s 
acceleration, a = -7.00m/s^2
displacement, s - 92m 
Using v^2 = u^2 - 2as 
0^2 - u^2 + 2 (-7.00) (92) 
initial velocity, u = sqrt (1288) = 35.9 m/s 
This is the speed pf the car just bore braking. 

I hope this helps!! 

You might be interested in
According to ____, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on other variable
irakobra [83]

Answer:

Signal detection theory

Explanation:

Signal detection theory states that stimulus ca be detected according to its intensity and a person's psychological and/or physical state. This means that we can notice things according to how strong they are but also, a person's characteristics like experience and physiological state like fatigue can affect the ability to detect them.

Because of this, the answer is that according to signal detection theory, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on other variables such as the level of noise in the system and your expectations.

8 0
3 years ago
Which of these diagrams best represents the steps in the formation of planets?
sineoko [7]
The right answer for the question that is being asked and shown above is that: "<span>C) The clouds of dust and gases rotate at high speed > The clouds condense > The sun is born > The planets are born " This is the </span><span>diagram that best represents the steps in the formation of planets</span>
6 0
3 years ago
Read 2 more answers
A very delicate sample is placed 0.150 cm from the objective lens of a microscope. The focal length of the objective is 0.140 cm
iVinArrow [24]

Answer:

m = 14*26 = 364

Explanation:

overall magnification is given as m

m = m_{o}* m_{e}

mo magnification of objective lens

me magnification of EYE lens

where mo is given as

m_{o} = \frac{v_{o}}{-u _{0}}

and me as

m_{e} = 1+\frac{D}{f_{e}}

d is distant of distinct vision = 25.0 cm for normal eye

fe =  focal length of eye piece

focal length of objective lense is 0.140 cm

we know that

\frac{1}{v_{0}}-\frac{1}{u_{0}}=\frac{1}{f_{0}}

\frac{1}{v_{0}} = \frac{1}{u_{0}} + \frac{1}{f_{0}}

\frac{1}{v_{0}} = \frac{1}{0.150} + \frac{1}{0.14}

\frac{1}{v_{o}} = 2.1 cm

m_{o} = \frac{2.1}{0.150} = 14

m_{e} = 1+\frac{25}{1}

m_{e} =26

m = m_{o}* m_{e}

m = 14*26 = 364

4 0
3 years ago
If an otherwise empty pressure cooker is filled with air of room temperature and then placed on a hot stove, what would be the m
Margaret [11]

Ideal Gas Law is, pV = NkbT

<span>Therefore, p/t  = Nkb/V which is equal to the constant</span>

We need to convert the given temperature to Kelvin. We need to add 273 to have the Kelvin of the temperature from Celsius.

T1= 20 + 273 = 293 K

T2= 120 + 273 = 393 K

With this we have the pressure ration of 393/293.

So,F120 = 1.34 APa

<span> </span>

6 0
3 years ago
A 2.0 µF capacitor is charged through a 50,000 ohm resistor. How long does it take for the capacitor to reach 90% of full charge
Nesterboy [21]

Answer:

0.23 s

Explanation:

First of all, let's find the time constant of the circuit:

\tau=RC

where

R=50,000 \Omega is the resistance

C=2.0\mu F=2.0\cdot 10^{-6}F is the capacitance

Substituting,

\tau=(50,000 \Omega)(2.0\cdot 10^{-6}F)=0.1 s

The charge on a charging capacitor is given by

Q(t)=Q_0 (1-e^{-t/\tau} ) (1)

where

Q_0 is the full charge

we want to find the time t at which the capacitor reaches 90% of the full charge, so the time t at which

Q(t)=0.90 Q_0

Substituting this into eq.(1) we find

0.90 Q_0 = Q_0 (1-e^{-t/\tau})\\0.90=1-e^{-t/\tau}\\e^{-t/\tau}=1-0.90=0.10\\-\frac{t}{\tau}=ln(0.10)\\t=-\tau ln(0.10)=(0.1 s)ln(0.10)=0.23 s

4 0
3 years ago
Other questions:
  • A parallel plate flow chamber is being designed to study the adhesion of leukocytes to endothelium. The channel width is 2cm; th
    11·1 answer
  • A spring with a force constant of 120 N/m is used to push a 0.27-kg block of wood against a wall
    8·1 answer
  • 34.6 cL= (blank) hL convert
    12·1 answer
  • If we assume that, in the African savanna, the predator population remains constant, what other, nonmobile, factor would influen
    7·1 answer
  • An undersea research chamber is spherical with an external diameter of 5.50 m . The mass of the chamber, when occupied, is 87600
    11·1 answer
  • A video game includes an asteroid that is programmed to move in a straight line across a 17-inch monitor according to the equati
    9·1 answer
  • An electron moves in a circular path perpendicular to a uniform magnetic field with a magnitude of 2.14 mT. If the speed of the
    7·1 answer
  • During the new moon phase, why is the Moon not visible in the sky?
    7·1 answer
  • please help! easy science! second pic is the question and possible answers (A B C or D) its one question! brainliest promised!
    10·1 answer
  • A magnet gets demagnetized when it is heated.​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!