All categories

3 years ago

Calculate the current through a 3.0 Ď‰ resistor with a voltage of 9.0 v across it.

Physics

1 answer:

gulaghasi [49]3 years ago

7 0

Answer: 3 A

Explanation:

According to<u> Ohm's law</u>:

$V=R.I$

Where:

$V=9 V$ is the voltage

$R=3\Omega$ is the resistance of the resistor

$I$ is the electric current (the value we want to find)

Isolating $I$ :

$I=\frac{V}{R}$

$I=\frac{9 V}{3\Omega}$

Finally:

$I=3 A$

You might be interested in

Of the following systems, which contains the most heat?

densk [106]

Answer:d

Explanation:

Given systems are state of matter and do not contain any heat instead Heat is required to change Phase or raise the temperature of the particular system.

For example 600 kg of ice at $0^{\circ}C$

Heat Required to convert it to water at $0^{\circ}C$ is

$Q=m\times L$

Where L=latent heat of Fusion $=334 J/gm$

$Q=600\times 334\times 1000$

$Q=200.4 MJ$

8 0

3 years ago

A solid conducting sphere with radius R carries a positive total charge Q. The sphere is surrounded by an insulating shell with

Illusion [34]

Answer:

Explanation:

Volume of the insulating shell is,

$V_{shell}=\frac{4}{3}\pi(R^3_2-R^3_1)$

Charge density of the shell is,

$\rho=\frac{Q_{shell}}{\frac{4}{3}\pi(R^3_2-R^3_1)}$

Here, $R_2 =2R, R_1 =R \,and\, Q_{shell} =-Q$

$\rho=\frac{Q_{shell}}{\frac{4}{3}\pi((2R)^3-R^3)}=\frac{-3Q}{28\piR^3}$

The electric field is $E=\frac{1}{4\pi\epsilon_0}\frac{Qr}{R^3}$

For 0 <r<R the electric field is zero, because the electric field inside the conductor is zero.

For R <r <2R According to gauss law

$E(4\pi r^2)=\frac{Q}{\epsilon_0}+\frac{4\pi\rho}{3\epsilon_0}(r^3-R^3)$

substitute $\rho=\frac{-3Q}{28\piR^3}$

$E=\frac{2}{7\pi\epsilon_0}\frac{Q}{r^2}-\frac{Qr}{28\piR^3}$

The net charge enclosed for each r in this range is positive and the electric field is outward

For r>2R

Charge enclosed is zero, so electric field is zero

8 0

3 years ago

Two charged spheres are 20cm apart and exert an attractive force of 6x10^-9 N on each other. What will be the force of attractio

Travka [436]

The force of attraction between 2 charged spheres can be explained by Coulomb's law,
It states the force of attraction is directly proportional to the magnitudes of the charges and inversely proportional to the square of the distance between the charges.

/ $F = \frac{k q_{1} q_{2} }{ r^{2} }$
where F - force of attraction/repulsion
q₁ and q₂ - charges of the 2 spheres
k - Coulomb's law constant
r - distance between the spheres

In the question given, the charges of the spheres remain constant in both instances, only distance changes. Therefore (kq₁q₂) = c which is a constant
then F = c / r²
first instance
6 x 10⁻⁹ N = c/ (20 cm)² ---1)
F = c/(10 cm)² --- 2)
2) / 1)
$\frac{F}{6* 10^{-9} } = \frac{400}{100}$
F = 6 x 10⁻⁹ x 4
F = 2.4 x 10⁻⁸ N

8 0

3 years ago

a car moves 6 km east, then 4km north. what was the distance covered? What was the total displacement?

Aliun [14]

Answer:

distance= 10 km

displacement= 7.21 km

Explanation:

distance= scalar (only magnitude)

displacement= vector (magnitude & direction)

distance= 6 km+ 4 km

= 10 km

displacement= shortest difference btwn 2 pts=

sqrt( 6^2+4^2)

sqrt(52)

7.21 km

7 0

2 years ago

A power cycle operates between a lake’s surface water at a temperature of 300 K and water at a depth whose temperature is 285 K.

nikdorinn [45]

Answer: a) 0.04kW = 40W

b) 0.05

Explanation:

Thermal efficiency of the power cycle = Input / output

Input = 10 kW + 14,400 kJ/min = 10 kW + 14,400 kJ/(60s) = 10 kW + 14,400/60 kW.

Output = 10 kW

Thermal Efficiency = Output / Input = 10kW / 250kW = 0.04KW = 40W

Maximum Thermal Efficiency of the power cycle = 1 - T1/T2

Where T1 = 285kelvin

And T2 = 300kelvin

Maximum Thermal Efficiency = 1 - T1/T2 = 1 - 285/300 = 0.05

8 0

3 years ago

Read 2 more answers