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3 years ago

Explain how magnets have an attractive force and repulsive force

1 answer:

7 0

The force between two parallel wires carrying currents in the same direction is attractive. It is repulsive if the currents are in opposite directions.

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When light shines through atomic hydrogen gas, it is seen that the gas absorbs light readily at a wavelength of 91.63 nm. What i

Artist 52 [7]

Answer:

D) 21

Explanation:

When gas absorbs light , electron at lower level jumps to higher level .

and the difference of energy of orbital is equal to energy of radiation absorbed.

Here energy absorbed is equivalent to wavelength of 91.63 nm

In terms of its energy in eV , its energy content is eual to

1243.5 / 91.63 = 13.57 eV. This represents the difference the energy of orbit .

Electron is lying in lowest or first level ie n = 1.

Energy of first level

= - 13.6 / 1² = - 13.6 eV.

Energy of n th level = - 13.6 / n². Let in this level electron has been excited

Difference of energy

= 13.6 - 13.6 / n² = 13.57 ( energy of absorbed radiation)

13.6 / n² = 13.6 - 13.57 = .03

n² = 13.6 / .03 = 453

n = 21 ( approx )

4 0

3 years ago

A coil of wire with 50 turns lies in the plane of the page and has an initial area of 0.140 m2. The coil is now stretched to hav

DENIUS [597]

Answer:

Magnitude of induced emf will be 87.5 volt

Direction of induced emf will be clockwise

Explanation:

We have given number of turns in the coil N = 50

Initial area $A=0.140m^2$

Time is given dt = 0.1 sec

Magnetic field B = 1.25 T

From Faraday's law of electromagnetic induction

n $e=-N\frac{d\Phi }{dt}=-NA\frac{dB}{dt}$

$e=-50\times 0.140\times \frac{1.25}{0.1}=-87.5volt$

So magnitude of induced emf is 87.5 volt

Direction of induced emf will be clockwise

7 0

4 years ago

An alpha particle has a charge of +2e and a mass of 6.64 x 10-27 kg. It is accelerated from rest through a potential difference

kondor19780726 [428]

Answer:

a) v = 1.075*10^7 m/s

b) FB = 7.57*10^-12 N

c) r = 10.1 cm

Explanation:

(a) To find the speed of the alpha particle you use the following formula for the kinetic energy:

$K=qV$ (1)

q: charge of the particle = 2e = 2(1.6*10^-19 C) = 3.2*10^-19 C

V: potential difference = 1.2*10^6 V

You replace the values of the parameters in the equation (1):

$K=(3.2*10^{-19}C)(1.2*10^6V)=3.84*10^{-13}J$

The kinetic energy of the particle is also:

$K=\frac{1}{2}mv^2$ (2)

m: mass of the particle = 6.64*10^⁻27 kg

You solve the last equation for v:

$v=\sqrt{\frac{2K}{m}}=\sqrt{\frac{2(3.84*10^{-13}J)}{6.64*10^{-27}kg}}\\\\v=1.075*10^7\frac{m}{s}$

the sped of the alpha particle is 1.075*10^6 m/s

b) The magnetic force on the particle is given by:

$|F_B|=qvBsin(\theta)$

B: magnitude of the magnetic field = 2.2 T

The direction of the motion of the particle is perpendicular to the direction of the magnetic field. Then sinθ = 1

$|F_B|=(3.2*10^{-19}C)(1.075*10^6m/s)(2.2T)=7.57*10^{-12}N$

the force exerted by the magnetic field on the particle is 7.57*10^-12 N

c) The particle describes a circumference with a radius given by:

$r=\frac{mv}{qB}=\frac{(6.64*10^{-27}kg)(1.075*10^7m/s)}{(3.2*10^{-19}C)(2.2T)}\\\\r=0.101m=10.1cm$

the radius of the trajectory of the electron is 10.1 cm

6 0

4 years ago

Design a modified priority encoder that receives an 8-bit input, A7:0and produces a 3-bit output, Y2:0. Y indicates the most sig

cupoosta [38]

Answer:

Explanation:

The first image that I attached to this solution is the diagram of a truth table for an 8 to 3 bit encoder.

The second image gives a sketch of the schematic.

The Boolean expression for the priority encoder including its zero inputs is defined in the third image attached.

Below is a snippet of the code for an 8 to 3 bit Priority encoder:

library IEEE;

use IEEE.STD_LOGIC_1164.all;

entity encoder8_3 is

port(

din : in STD_LOGIC_VECTOR(7 downto 0);

dout : out STD_LOGIC_VECTOR(2 downto 0)

);

end encoder8_3;

architecture encoder8_3_arc of encoder8_3 is

begin

dout <= "000" when (din="10000000") else

"001" when (din="01000000") else

"010" when (din="00100000") else

"011" when (din="00010000") else

"100" when (din="00001000") else

"101" when (din="00000100") else

"110" when (din="00000010") else

"111";

end encoder8_3_arc;

3 0

3 years ago

Explain why an egg cooks more slowly in boiling water in Denver than in New York City. (Hint: Consider the effect of temperature

stiv31 [10]

Answer:

In New York is at ocean level while Denver is at an altitude of 1 mile from ocean level. In this way, the breaking point of water is lower in Denver than in New York, that is, the water will boil at lower temperatures in Denver than in New York. If the breaking point of the water decreases, at this point it will put aside more effort to cook an egg. Now the time required to cook the egg is higher in Denver than in New York.

6 0

3 years ago