Atoms Test

Result

Atoms Test - 34

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

How can the brightness of the pattern on the screen of cathode ray tube be changed?

A
Changing the target

B
By changing the current on grid

C
By changing the negative potential on grid

D
Can't be changed

Solution

Since the brightness or intensity of the display depends on the number of electrons that strike the screen, the control grid is used to control the brightness of the CRT.
Question 2
1 / -0

If a nucleus such as $$^{226}Ra$$, that is initially at rest, undergoes $$\alpha-decay$$, then which of the following statement is true?

A
The alpha particle has more kinetic energy then the daughter nucleus

B
The alpha particle has less kinetic energy then the daughter nucleus

C
The alpha particle and daughter nucleus both have same kinetic energy

D
We cannot say anything about kinetic energy of alpha particle and daughter nucleus

Solution

The momentum of the system will be conserved as there is zero external force.
Assume $$^{226} Ra$$ is recoiled with momentum $$P_{Ra}$$ and $$\alpha$$ particle has momentum $$P_\alpha$$ From momentum conservation:

$$P_{Ra}$$$$ =P_\alpha$$

Kinetic energy is given by $$K.E. =\dfrac{P^2}{2m}$$

As momentum is same in both the nucleus and $$\alpha$$ particle kinetic energy is inversely proportional to mass $$\alpha$$ particle will have more kinetic energy since it has lower mass compared to nucleus.
Question 3
1 / -0

The angular momentum of an electron in an orbit is quantized because it is a necessary condition for the compatibility with

A
Wave nature of electron

B
Particle nature of electron

C
Pauli's exclusion behaviour

D
None of these

Solution

Quantization of angular momentum comes from the particle nature of electrons, and all of its postulates.
Question 4
1 / -0

Mark out the incorrect statement :

A
A free neutron can transform itself into photon

B
A free proton can transform itself into neutron

C
In beta minus decay, the electron originates from nucleus

D
All of the above

Solution

In beta minus decay, a neutron decays into a proton, an electron.
A free neutron is unstable, decaying to a proton, electron and antineutrino.
Inside a nucleus, a proton can transform into a neutron via inverse beta.
Question 5
1 / -0

The diagram below shows a cathode ray tube in which the arrow indicates a beam of charged particles approaching an electric field between the plates A and B. State the approximate potential difference applied between the anode and filament.

A
250 V

B
500 V

C
1000 V

D
None of the above

Solution

Anode and filament potential should be high enough to accelerate the electrons in the electron gun. It should be in the order of $$10^3$$
Question 6
1 / -0

Directions For Questions

In a cathode ray tube, give reason for the following :

...view full instructions

the anode is kept at positive potential with respect to the cathode.

A
themions are get attracted towards the anode and accelerate towards the anode

B
themions are get deviated towards the anode and accelerate towards the anode

C
themions get attracted towards the cathode and accelerate towards the cathode

D
none of these

Solution

The themions are get attracted towards the anode and accelerate towards the anode due to the potential difference between anode and cathode.
Question 7
1 / -0

The diagram below shows a cathode ray tube in which the arrow indicates a beam of charged particles approaching an electric field between the plates A and B. State the amount of charge on each particle.

A
$$1.6\, \times\, 10^{-19} C$$

B
$$-1.6\, \times\, 10^{-19} C$$

C
0

D
$$-1.16\, \times\, 10^{-19} C$$

Solution

The beam of charged particles in the cathode ray tube experiment is an electron beam, hence the charge on each particle equals $$-1.6 \times 10^{-19} \ C$$
Question 8
1 / -0

The diagram below shows a cathode ray tube in which the arrow indicates a beam of charged particles approaching an electric field between the plates A and B. State the approximate voltage $$V_1$$ used to heat the filament.

A
1.5 V

B
3 V

C
6 V

D
12 V

Solution

Thermal energy given to the charge carriers overcome the work function of the metal surface and thus flow of charge carriers (electrons) takes place from the metal surface. The work function of the tungsten filament used is $$4.5 eV$$. Thus to overcome this work function, a slightly higher potential is applied to heat the filament which is $$6V$$.
Question 9
1 / -0

Diagram shows an electron gun inside a cathode ray tube. Which of the following is true?

A
F is Filament, to heat the cathode X

B
X is Cathode, to emit the electrons

C
Y is Anode, to provide kinetic energy to electrons

D
All the above

Solution

As the current is passed through the filament F, which gets heated and increase the temperature of cathode X, which upon heating shows photoelectric effect and emit electrons towards the anode Y. Anode is at higher potential and provide kinetic energy to electrons.
Question 10
1 / -0

In a cathode ray tube, the screen is coated with fluorescent material.

A
it produces spots on the screen

B
beam of light is not in a straight line

C
light deviates away after striking

D
none of these

Solution

When the electron beam strikes the screen coated with fluorescent material the electrical signals appear as visual pattern or spots on the screen.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Atoms Test - 34

Result

Atoms Test - 34

Score

-

Rank

-

SHARING IS CARING

Question 1

Changing the target

By changing the current on grid

By changing the negative potential on grid

Can't be changed

Solution

Question 2

The alpha particle has more kinetic energy then the daughter nucleus

The alpha particle has less kinetic energy then the daughter nucleus

The alpha particle and daughter nucleus both have same kinetic energy

We cannot say anything about kinetic energy of alpha particle and daughter nucleus

Solution

Question 3

Wave nature of electron

Particle nature of electron

Pauli's exclusion behaviour

None of these

Solution

Question 4

A free neutron can transform itself into photon

A free proton can transform itself into neutron

In beta minus decay, the electron originates from nucleus

All of the above

Solution

Question 5

250 V

500 V

1000 V

None of the above

Solution

Question 6

themions are get attracted towards the anode and accelerate towards the anode

themions are get deviated towards the anode and accelerate towards the anode

themions get attracted towards the cathode and accelerate towards the cathode

none of these

Solution

Question 7

$$1.6\, \times\, 10^{-19} C$$

$$-1.6\, \times\, 10^{-19} C$$

0

$$-1.16\, \times\, 10^{-19} C$$

Solution

Question 8

1.5 V

3 V

6 V

12 V

Solution

Question 9

F is Filament, to heat the cathode X

X is Cathode, to emit the electrons

Y is Anode, to provide kinetic energy to electrons

All the above

Solution

Question 10

it produces spots on the screen

beam of light is not in a straight line

light deviates away after striking

none of these

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.