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
Ulleksa [173]
3 years ago
11

9. A car driver brakes gently. Her car slows down front --

Physics
1 answer:
sleet_krkn [62]3 years ago
7 0

Answer:

9) This is a case of deceleration

10)-0.8 ms-2

b) acceleration is the change in velocity with time

11)

a) 100 ms-1

b) 100 seconds

12) 10ms-1

13) more information is needed to answer the question

14) - 0.4 ms^-2

15) 0.8 ms^-2

Explanation:

The deceleration is;

v-u/t

v= final velocity

u= initial velocity

t= time taken

20-60/50 =- 40/50= -0.8 ms-2

11)

Since it starts from rest, u=0 hence

v= u + at

v= 10 ×10

v= 100 ms-1

b)

v= u + at but u=0

1000 = 10 t

t= 1000/10

t= 100 seconds

12) since the sprinter must have started from rest, u= 0

v= u + at

v= 5 × 2

v= 10ms-1

14)

v- u/t

10 - 20/ 25

10/25

=- 0.4 ms^-2

15)

a=v-u/t

From rest, u=0

8 - 0/10

a= 8/10

a= 0.8 ms^-2

You might be interested in
Which of these correctly shows what happens when two magnets are placed side by side?
Margarita [4]

Answer:

D

Explanation:

Remember that magnets only attract at different poles. If both poles are the same, they repel

3 0
3 years ago
Which term describes an experiment with one dependent variable and one experimental variable
wlad13 [49]
A. Controlled experiment hope this helps
8 0
3 years ago
Read 2 more answers
A straight section of silver wire has a cross sectional area A=2.0 mm2. A total of 9.4×1018 electrons pass through the wire in 3
Sergio [31]

Answer:

8.08 x 10^-5 m

Explanation:

A = 2 mm^2 = 2 x 10^-6 m^2

Total number of electrons, N = 9.4 x 10^18

time, t = 3 s

n = 5.8 x 10^28 electrons/ m^3

Current, i = Q / t = N x e / t = (9.4 x 10^18 x 1.6 x 10^-19) / 3 = 0.5 A

Let vd be the drift velocity.

i = n e A vd

0.5 = 5.8 x 10^28 x 1.6 x 10^-19 x 2 x 10^-6 x vd

vd = 2.7 x 10^-5 m/s

Distance traveled by the electrons = velocity x time

                                                          = vd x t = 2.7 x 10^-5 x 3 = 8.08 x 10^-5 m  

3 0
3 years ago
Discuss the phase change condition due to reflection of light from a surface. Summarize equations of interference for thin film.
Dmitrij [34]

Answer:

if this surface has a higher index than in the medium where the light travels, the reflected wave has a phase change of 180º

Explanation:

When a ray of light falls on a surface if this surface has a higher index than in the medium where the light travels, the reflected wave has a phase change of 180º this can be explained by Newton's third law, the light when arriving pushes the atoms of the medium that is more dense, and these atoms respond with a force of equal magnitude, but in the opposite direction.

When the fractional index is lower than that of the medium where the reflacted beam travels, notice a change in phase.

Also, when light penetrates the medium, it modifies its wavelength

              λ = λ₀ / n

We take these two aspects into account, the condition for contributory interference is

            d sin θ = (m + 1/2) λ

for destructive interference we have

            d sin θ = m λ

in general this phenomenon is observed at 90º

           2 d = (m +1/2) λ° / n

          2nd = (m + ½) λ₀

5 0
3 years ago
A manufacturer claims that a carpet will not generate more than 5.8 kV of static electricity What magnitude of charge would have
DiKsa [7]

Answer:

4.4×10⁻⁷ Coulomb

Explanation:

V = Voltage = 5.8 kV

d = Potential distance = 2.8 mm = 0.0028 m

A = Area = 0.3×0.08 = 0.024 m²

ε₀ = permittivity constant in a Vacuum= 8.85×10⁻¹² F/m

\frac{Q}{V}=\frac{A\epsilon_0}{d}\\\Rightarrow \Q=V\frac{A\epsilon_0}{d}\\\Rightarrow Q=5.8\times 10^3\frac{0.024\times 8.85\times 10^{-12}}{0.0028}\\\Rightarrow Q=4.4\times 10^{-7}\ C

Magnitude of charge transferred between a carpet and a shoe is 4.4×10⁻⁷ Coulomb.

6 0
3 years ago
Other questions:
  • A +4.0- μC charge is placed on the x axis at x = +3.0 m, and a −2.0- μC charge is located on the y axis at y = −1.0 m. Point A i
    9·1 answer
  • The passing of the Moon directly between Earth and the Sun is a/an
    5·1 answer
  • A ray diagram without the produced image is shown.
    7·2 answers
  • The law of reflection states that if the angle of incidence is 76 degrees, the angle of reflection is ___ degrees.
    7·1 answer
  • Suppose the counter attendant pushes a 0.27 kgkg bottle with the same initial speed on a different countertop and it travels 1.7
    11·1 answer
  • A converging lens focuses a set of light rays entering the lens on one side parallel to its axis to a single focal point on the
    10·1 answer
  • What are the advantages of parallel circuits? Check all that apply
    11·2 answers
  • Choose the incorrect statement about the proton: Group of answer choices The proton has the atomic mass of 1 amu The proton has
    15·1 answer
  • What is the name of the theory that explains how forces deep within earth can cause ocean floors to spread continents to move
    8·1 answer
  • Which choice best describes how scientists learn new information during investigations?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!