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
BartSMP [9]
3 years ago
9

What will the surface charge density be if the radius of the disk is doubled but its total charge remains the same

Physics
1 answer:
zaharov [31]3 years ago
8 0

Answer:

the new surface charge density = Q/4πr²( initial surface charge density divided by 4)

Explanation:

charge density(surface) = Q/A = charge/area

let r be the initial radius of the disk

therefore, area A = πr²

charge density = Q/πr²

Now that the radius is doubled, let it be represented as R

∴ R = 2r

Recall, charge density = Q/A

A = πR = π(2r)² = 4πr²

the new surface charge density = Q/4πr²

the initial surface charge density divided by 4

You might be interested in
A car traveling with constant speed travels 150 km in 7200s what is the speed of the car
Oksana_A [137]
Velocity is distance/time 

so 150/7200=.0208km/s 

unless you have to convert it to miles or something else. but use the formula!
5 0
3 years ago
A private aviation helicopter's main rotor blades rotate at approximately
Arisa [49]

Answer: 7.5 rev/s

Explanation:

We are given the angular velocity \omega a helicopter's main rotor blades:

\omega=450 rpm=450 \frac{rev}{min}

However, we are asked to express this \omega in the International Systrm (SI) units. In this sense, the SI unit for time is second (s):

\omega=450 \frac{rev}{min} \frac{1 min}{60 s}

\omega=7.5 \frac{rev}{s}

4 0
2 years ago
A bicyclist of mass 112 kg rides in a circle at a speed of 8.9 m/s. If the radius of the circle is 15.5 m, what is the centripet
kogti [31]
The centripetal force, Fc, is calculated through the equation, 
                                    Fc = mv²/r
where m is the mass,v is the velocity, and r is the radius. 
Substituting the known values,
                                     Fc = (112 kg)(8.9 m/s)² / (15.5 m)
                                         = 572.36 N
Therefore, the centripetal force of the bicyclist is approximately 572.36 N. 
4 0
3 years ago
Read 2 more answers
How much potential energy does a 40n block medicine ball gain when it is lifted 5.m
MAVERICK [17]
By definition, the gain in PE (potential energy) is
ΔPE = m*g*h

Given:
mg = 40 N  (Note that m*g = weight)
h = 5 m

ΔPE = (40 N)*(5 m) =200 J

Answer: 200 J

5 0
3 years ago
Read 2 more answers
A viscous fluid is flowing through two horizontal pipes. They have the same length, although the radius of one pipe is three tim
Rudik [331]

The conservation of the mass of fluid through two sections (be they A1 and A2) of a conduit (pipe) or current tube establishes that the mass that enters is equal to the mass that exits. Mathematically the input flow must be the same as the output flow,

Q_1 = Q_2

The definition of flow is given by

Q =VA

Where

V = Velocity

A = Area

The units of the flow of flow are cubic meters per second, that is to say that if there is a continuity, the volume of input must be the same as that of output, what changes if the sections are modified are the proportions of speed.

In this way

Q_A = Q_B

Q_B = 2.94*10^2 m^3/s

7 0
3 years ago
Other questions:
  • True or false ??
    10·2 answers
  • Select the correct text in the passage.
    9·2 answers
  • Plane microwaves are incident on a thin metal sheet that has a long, narrow slit of width 4.8 cm in it. The microwave radiation
    11·1 answer
  • What is massand its si unit​
    8·1 answer
  • A 2,493-kg car is moving down a road with a slope (grade of 14% at a constant speed of 13 m/s. what is the direction and magnitu
    6·1 answer
  • In the design of a supermarket, there are to be several ramps connecting different parts of the store. Customers will have to pu
    6·1 answer
  • Sound waves require a medium to travel through, such as a solid, liquid or gas because
    5·2 answers
  • Please I need with this
    14·1 answer
  • explain why an inflated balloon is likely to burst if you leave it near a window with the sun streaming it?
    7·1 answer
  • The speed of an object increases by 30 m/s in 10 seconds. what is its acceleration?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!