Explain why scissors for cutting cloth may have blades much longer than the handles; but shears for cutting metals have short blades and long handles? 

A woman draws water from well using a fixed pulley. The mass of the bucket and water together is 6.0 kg. the force applied by the woman is 70 N. Calculate the mechanical advantage. 

State the energy changes in an oscillating pendulum.

Two bulls of mass ratio 1:2are dropped from the same height.

1. State the ratio between their velocities when they strike the ground and

A piece of ice floating in a glass of water but the level of water in the glass of water melts but the level of water in the glass does not change.  Explain this phenomenon. 

An inflated gas balloon is placed in a jar, which is connected to an evacuating pump. What will be observed if the air bubble inside the jar is pumped out? Give a reason justifying your answers. 

Define ‘critical angle’.

8.

A ray of light passes through a right-angled prism as shown in the figure. State the angles of incidence at the face of AC and BC.

1. White light is passed through a yellow filter. What colour is (colours are) seen on a screen placed at the end.

2. If the light emerging from the yellow filter is then passed through red filter, what will be seen on the screen placed at the end?

What is SONAR? State the principle on which it is based.