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
tensa zangetsu [6.8K]
3 years ago
7

A converging lens of focal length 20 cm is placed in contact with a diverging lens of focal length 30 cm. The focal length of th

is combination is
Physics
1 answer:
kramer3 years ago
7 0

Answer:

The focal lenth (F) =+10.0cm

Explanation:

The formular for combined focal length (F) is given as;

1/f = 1/f_{1} + 1/f_{2}

In this  question,

F1 = 20cm

F2  = -30cm

Plugging the values into the formuar above,

1/f = 1/20 + 1/(-30)

1/f = 0.05 - 0.033[tex]1/f = -0.017f = [tex]1/ -0.017

f = 58.82cm

i.e. the combination behaves as a converging lens (because of the postive sign) of focal length 58.82cm .

You might be interested in
1) A car is moving to the right with the constant speed of 1.2 m/s. If the car starts
Marina CMI [18]
(100, 108)
Due to
1.2x90=108

100, 108
7 0
3 years ago
If you cut a piece of wood in half, each half would have *
Anon25 [30]

Answer:

c

Explanation:

let's assume that you are splitting the piece of wood horizontally. This would not change the density of the wood at all, only the length. I rest my case. Ur awesome and have an amazing day.

7 0
3 years ago
A mango falls fromthe top its tree passing a window which is 2.4m tall by taking 0.4s
Natasha2012 [34]

Explanation:

There are three points in time we need to consider.  At point 0, the mango begins to fall from the tree.  At point 1, the mango reaches the top of the window.  At point 2, the mango reaches the bottom of the window.

We are given the following information:

y₁ = 3 m

y₂ = 3 m − 2.4 m = 0.6 m

t₂ − t₁ = 0.4 s

a = -9.8 m/s²

t₀ = 0 s

v₀ = 0 m/s

We need to find y₀.

Use a constant acceleration equation:

y = y₀ + v₀ t + ½ at²

Evaluated at point 1:

3 = y₀ + (0) t₁ + ½ (-9.8) t₁²

3 = y₀ − 4.9 t₁²

Evaluated at point 2:

0.6 = y₀ + (0) t₂ + ½ (-9.8) t₂²

0.6 = y₀ − 4.9 t₂²

Solve for y₀ in the first equation and substitute into the second:

y₀ = 3 + 4.9 t₁²

0.6 = (3 + 4.9 t₁²) − 4.9 t₂²

0 = 2.4 + 4.9 (t₁² − t₂²)

We know t₂ = t₁ + 0.4:

0 = 2.4 + 4.9 (t₁² − (t₁ + 0.4)²)

0 = 2.4 + 4.9 (t₁² − (t₁² + 0.8 t₁ + 0.16))

0 = 2.4 + 4.9 (t₁² − t₁² − 0.8 t₁ − 0.16)

0 = 2.4 + 4.9 (-0.8 t₁ − 0.16)

0 = 2.4 − 3.92 t₁ − 0.784

0 = 1.616 − 3.92 t₁

t₁ = 0.412

Now we can plug this into the original equation and find y₀:

3 = y₀ − 4.9 t₁²

3 = y₀ − 4.9 (0.412)²

3 = y₀ − 0.83

y₀ = 3.83

Rounded to two significant figures, the height of the tree is 3.8 meters.

6 0
3 years ago
A gas is compressed from an initial volume of 5.75 L to a final volume of 1.23 L by an external pressure of 1.00 atm. During the
nataly862011 [7]

Answer:

<em>The internal energy change is 330.01 J</em>

Explanation:

Given

v_{1} the initial volume = 5.75 L

v_{2} the final volume = 1.23 L

P_{e} is the external pressure = 1.00 atm

q the heat energy removed = -128 J (since is removed from the system)

expansion against a constant external pressure is an example of an irreversible pathway, here pressure in is greater than pressure out and can be obtained thus;

W = -P_{e}ΔV

W = -1.00 x(1.23 - 5.75)

W =  -1.00 x -4.52

W = 4.52 L atm

converting to joules we have

W = 4.52 L atm x 101.33 J/ L atm = 458.01 J

The internal energy change during compression can be calculated thus;

ΔU = q + W

ΔU = -128 J + 458.01 J

ΔU = 330.01 J

Therefore the internal energy change is 330.01 J

8 0
3 years ago
2 questions, brainliest for both correct! please: only answer if you are sure of the answer!! :)
Pani-rosa [81]

Answer:

Explanation:

1. B

2.D

5 0
3 years ago
Read 2 more answers
Other questions:
  • Adults with Down syndrome can often find work because they have received _____.
    11·2 answers
  • Which of the following is an example of an anaerobic exercise?
    8·1 answer
  • A student is pouring equal amounts of water, maple syrup, and cooking oil into a glass beaker and looking at how the layers sett
    15·1 answer
  • Magnesium oxide is a binary ionic compound. From its formula, MgO, how do you know that Mg is the metal?
    6·2 answers
  • If AB has a bearing of following 234° 51' 48" and a anti-clockwise angle from AB to C is measured as 80° Calculate the bearing A
    11·1 answer
  • a body of mass 1.5kg, traveling along the positive x axis with speed 4.5m/s,collides with another body B of mass 3.2kg which,ini
    7·1 answer
  • Has anyone ever done the model of an atom lab?
    8·2 answers
  • The coulombic force between two ions is reduced to ______ of its original strength when the distance between them is quadrupled.
    8·1 answer
  • I need help asap!!!!!!!!!!!!
    11·1 answer
  • Which season is signaled by average lower temperature and indirect, angled sunlight?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!