Radioactivity — Physics STD 10 — Question

A certain nucleus A (mass number 238 and atomic number 92) is radioactive and becomes a nucleus B (mass number 234 and atomic number 90) by the loss of one particle.

State the change in the form of a reaction.

How do kilowatt and kilowatt-hour differ ?

A metal ball of mass 2kg is allowed to fall freely from rest from a height of 5m above the ground.
What happens to the mechanical energy after the ball hits the ground and comes to rest ?

What is a.m.u ? Express 1 a.m.u. in MeV.

Define the term power of a lens. In what unit is it expressed?

Name the energy changes for the following:
pendulum

State the energy transformation on the following:
Electricity is obtained from hydro energy.

A convex lens forms an image of an object equal to the size of the object.Where is the object placed in front of the lens?

A physical balance has its arms of length 60 cm and 40 cm. What weight kept on pan of the longer arm will balance an object of weight 100 gf kept on other pan?

State one use of radio-isotopes.