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
lutik1710 [3]
4 years ago
15

Two lab partners, Mary and Paul, are both farsighted. Mary has a near point of 68.6 cm from her eyes and Paul has a near point o

f 128 cm from his eyes. Both students wear glasses that correct their vision to a normal near point of 25.0 cm from their eyes, and both wear glasses 1.80 cm from their eyes. In the process of wrapping up their lab work and leaving for their next class, they exchange glasses (Mary leaves with Paul's glasses and Paul leaves with Mary's glasses). When they get to their next class, find the following.
(a) Determine the distance to the closest object that Mary can see clearly (relative to her eyes) while wearing Paul's glasses.
(b) Determine the distance to the closest object that Paul can see clearly (relative to his eyes) while wearing Mary's glasses.
Physics
1 answer:
Misha Larkins [42]4 years ago
8 0

Answer:

a) 27.7 cm  

b) 19.9 cm

Explanation:

for mary  

d1i = 68.6-1.8 = 66.8 cm

d1o = 25-1.8 = 23.2 cm

1/f1 = 1/d1o + 1/d1i

1/f1 = -(1/23.2)-(1/66.8)

f1 = -17.22 cm

for paul

d2o = 25-1.8 = 23.2 cm

d2i = 128-1.8 = 126.2 cm

1/f2= 1/d2o + 1/d2i

1/f2 = -(1/23.2)-(1/126.2)

f2 = -19.6 cm

a)

1/do + 1/d1i = 1/f2

1/do - (1/66.8) = -1/19.6

do = 27.7 cm  

part b)

1/do + 1/d2i = 1/f1

1/do - (1/126.2) = -(1/17.22)

do = 19.9 cm

You might be interested in
A 24-cm circumference loop of wire has a resistance of 0.14 Ω. The loop is placed between the poles of an electromagnet, and a f
Triss [41]

Answer:

The induced current in the loop is 1.2 A

Explanation:

Given;

length of the wire, L = 24 cm = 0.24 m

resistance of the wire, R = 0.14 Ω.

magnetic field strength, B = 0.55 T

time, t = 15 ms = 15 x 10⁻³ s

Circumference of a circle is given as;

L = 2πr

0.24 = 2πr

r = 0.24 / 2π

r = 0.0382 m

Area of a loop is given as;

A = πr²

A = π (0.0382)²

A = 0.004585 m²

Induced emf is given as;

emf = -\frac{\delta \phi}{dt}

Ф = ΔB x A

Ф = ( 0 - 0.55 T) x 0.004585 m²

Ф = -0.002522 T.m²

emf = - (\frac{-0.002522}{15*10^{-3}} )\\\\emf = 0.168 \ V

According to ohm's law;

V = IR

Where;

I is current

The induced current in the loop is calculated as;

I = V / R

I = 0.168 / 0.14

I = 1.2 A

Therefore, the induced current in the loop is 1.2 A

4 0
3 years ago
The basic unit of electric current is the <br> .
Masja [62]
The Ampere (A). You could literally google to be more efficient, all the same to me tho
4 0
3 years ago
Read 2 more answers
A ________________ in a transverse wave corresponds to a compression in a longitudinal wave
cluponka [151]
The answer is Crest in transverse waves, this is where the particles are closest to each other due to the compression of the longitudinal component of the wave.
3 0
3 years ago
If it takes 320 N of force to push a box up a ramp, yet it would take 1,600 N of force to lift the box straight up, what is the
grin007 [14]
MA = Fwithout help/Fwith machine
MA = 1600/320 = 5
5 0
3 years ago
A satellite in a nearly circular orbit is 2000 km above earth's surface. the radius of earth is approximately 6400 km. if the sa
Ann [662]
Velocity is computed using the formula:

v= \frac{d}{t}
Where:
V = speed
d = distance traveled
t = time/period

First you need to consider that the orbit is circular. To get the measurement or the distance going around Earth, you will need to get the circumference of the path. 

C = 2 \pi r

Where:
C = circumference
π = 3.14
r = radius


The Earth has a radius of 6,400km, but you also need to consider that the satellite is orbiting above the surface of the Earth, so you add in the 2,000km to that radius. 

r = 6,400Km + 2,000Km = 8,400Km

Next step is to insert that into our circumference formula:

C = 2 \pi r
C = 2 \pi 8,400Km
C = 52,778.76 Km

The distance traveled would then be 52,778.76Km

Now that we have the distance, we can then get the velocity:

v= \frac{d}{t}
v= \frac{52,778.76Km}{12hrs}
v= 4,398.23km/hr

The speed of the satellite is 4,398.23km/hr.

7 0
3 years ago
Other questions:
  • A 6000 kg lorry is reversing into a parking space at a speed of 0.5 m/s but collides with a car. The crumple zone of the car sto
    8·2 answers
  • The electric force between two charged objects is influenced by _____.
    11·1 answer
  • Define the si units for length mass time and temperature
    5·1 answer
  • The energy of microwaves is less than the energy of ultraviolet light. Which comparison of the energies of electromagnetic waves
    15·1 answer
  • A wildebeest runs with an average speed of
    5·1 answer
  • How can scientists use seismographs to identify the location of an earthquake?
    6·1 answer
  • Your car is initially at rest when you hit that gas and the car begins to accelerate. The forward force of the car is 5630 N whi
    14·1 answer
  • What’s velocity and acceleration
    11·1 answer
  • What is the mass of a box that accelerates to 10 m/s/s with a 70 Newton push?
    6·1 answer
  • Classify each change (which can be manipulated within the green box) according to its effect on the wavelength.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!