NEET 2020 Exam Paper (180 Q) - Mock Test

For transistor action, which of the following statements is correct?

Light of frequency $1.5$ times the threshold frequency is incident on a photosensitive material. What will be the photoelectric current if the frequency is halved and intensity is doubled?

When a uranium isotope ${}_{92}^{235}\text{U}$ is bombarded with a neutron, it generates ${}_{36}^{89}\text{Kr}$, three neutrons and:

The energy required to break one bond in DNA is $10^{-20}\text{J}$. This value in $\text{eV}$ is nearly:

Two bodies of mass $4\text{kg}$ and $6\text{kg}$ are tied to the ends of a massless string. The string passes over a pulley which is frictionless. The acceleration of the system in terms of acceleration due to gravity ($g$) is: