Current Electricity — Physics STD 10 — Question

A lever of length 9 cm has its load arm 5 cm long and the effort arm is 9 cm long.
What will be the mechanical advantage and velocity ratio if the efficiency becomes 50% ?

Name the type of energy (kinetic energy K or potential energy U) possessed in the given cases:
A moving cricket ball

State the nature and position of the object on the principal axis to obtain a virtual and magnified image.

What is the main energy transformation that occur in:
Charging of a battery.

Name the waves which are used in sonar to find the depth of sea.

Name four colours of the spectrum of white light which have wavelength longer than blue light.

When do you use (i) Fleming's left hand rule, and (ii) Fleming's right hand rule?

State the energy changes which take place when Water stored in the dam is used to turn turbine in dynamo.

Can a simple machine act as a force multiplier and a speed multiplier at the same time?