41.

What is thermionic emission? 

Name the unit in which the work function of a metal is expressed? 

Complete the diagram as given above by drawing the deflection of radioactive radiation in an electric field. 

State any two precautions to be taken while handling radioactive substances. 

An atomic nucleus A is composed of 84 protons and 128 neutrons.

i) The nucleus A emits an alpha particle and is transformed into nucleus B. What is the composition of nucleus B?

ii) The nucleus B emits a beta particle and is transformed into a nucleus C. What is the composition of nucleus C?

A block and a tackle system has V.R. = 5

i) Draw a neat labelled diagram of a system indicating the direction of its load and effort

ii) Rohan exerts a pull of 150 kgf. What is the maximum load he can raise with this pulley system if it’s efficiency = 75%?

Name one factor that affects the lateral displacement of light as it passes through a rectangular glass slab. 

In the diagram alongside, A, B, C, D are four pendulums suspended from the same elastic string PQ. The length of A and C are equal to each other while the length of the pendulum B is smaller than that of D. Pendulum A is set into a mode of vibrations.

i) Name the type of vibrations taking place in pendulum B and D?

ii) What is the state of the pendulum C?