4. What is the formula for potassium dichromateo?b

How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 4.57×10−21 n

hichkok12 [17]

Answer:

891 excess electrons must be present on each sphere

Explanation:

One Charge = q1 = q

Force = F = 4.57*10^-21 N

Other charge = q2 =q

Distance = r = 20 cm = 0.2 m

permittivity of free space = eo =8.854×10−12 C^2/ (N.m^2)

Using Coulomb's law,

F=[1/4pieo]q1q2/r^2

F = [1/4pieo]q^2 / r^2

q^2 =F [4pieo]r^2

q = r*sq rt F[4pieo]

q=0.2* sq rt[ 4.57 x 10^-21]*[4*3.1416*8.854*10^-12]

q = 1.42614*10^ -16 C

number of electrons = n = q/e=1.42614*10^ -16 /1.6*10^-19

n =891

891 excess electrons must be present on each sphere

5 0

3 years ago

How Can the human ear detect the sound

mart [117]

Answer:

Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum. The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear.

8 0

3 years ago

When a police officer receives information that you are speeding in your vehicle, she is using the ______________ of the wave to

Alex

I think the corect answer would be C. When a police officer receives information that you are speeding in your vehicle, she is using the frequency of the wave to measure the Doppler Effect. As the speed of a vehicle increases, the greater the change of the frequency of the waves would be transmitted to the radar guns which is being used by the police officer. Doppler effect is an effect that is observed in sound and light waves as these waves move away or to the direction of the observer. This is being used in many applications like in astronomy, weather balloons, the radar guns,and for underwater researches.

6 0

3 years ago

A truck is moving around a circular curve at a uniform velocity of 13 m/s. If the centripetal force on the truck is 3,300 N and

Paladinen [302]

Answer: Option B.

Since here the truck is moving on a circular track, it will experience centripetal force.

F(centripetal) = m × acc
or
$r = \frac{m v^{2}}{F}$

where r is the radius of the track.
m is the mass of truck
v is the speed of the truck.
Given: v = <span>13 m/s
m = </span><span>1,600 kg
</span>F = 3300 Newton

To find = radius of track=?
$r = \frac{m v^{2} }{F}$
$r = \frac{1600*13*13}{3300}$
r = 81.94 m
Therefore, radius of track is 81.94 m

4 0

3 years ago

Read 2 more answers

1. A race car moves along a circular track of radius 100m at a velocity of 25m/s. (a) What is

goldenfox [79]

Given :

A race car moves along a circular track of radius 100m at a velocity of 25m/s.

To Find :

(a) What is the time taken to complete one lap of the circular track.

(b) What is the time taken for 10 laps.

Solution :

Circumference of circular track,