1
KCET 2023
MCQ (Single Correct Answer)
+1
-0

The energy gap of an LED is $$2.4 \mathrm{~eV}$$. When the LED is switched ON, the momentum of the emitted photons is

A
$$1.28 \times 10^{-27} \mathrm{~kg} \mathrm{~ms}^{-1}$$
B
$$2.56 \times 10^{-27} \mathrm{~kg} \mathrm{~ms}^{-1}$$
C
$$1.28 \times 10^{-11} \mathrm{~kg} \mathrm{~ms}^{-1}$$
D
$$0.64 \times 10^{-27} \mathrm{~kg} \mathrm{~ms}^{-1}$$
2
KCET 2023
MCQ (Single Correct Answer)
+1
-0

In the following equation representing $$\beta^{-}$$ decay, the number of neutrons in the nucleus $$X$$ is

$${ }_{83}^{210} \mathrm{Bi} \longrightarrow X+e^{-1}+\bar{v}$$

A
126
B
127
C
125
D
84
3
KCET 2023
MCQ (Single Correct Answer)
+1
-0

A nucleus with mass number 220 initially at rest emits an alpha particle. If the $$Q$$ value of reaction is $$5.5 ~\mathrm{MeV}$$. Calculate the value of kinetic energy of alpha particle

A
$$6.5 \mathrm{~MeV}$$
B
$$5.4 \mathrm{~MeV}$$
C
$$7.4 \mathrm{~MeV}$$
D
$$4.5 \mathrm{~MeV}$$
4
KCET 2023
MCQ (Single Correct Answer)
+1
-0

A particle is in uniform circular motion, related to one complete revolution of the particle, which among the statements is incorrect?

A
Average acceleration of the particle is zero.
B
Displacement of the particle is zero.
C
Average speed of the particle is zero.
D
Average velocity of the particle is zero.