ICSE ICSE Class 8 - CISCE Question Bank Solutions for Physics

Which of the following will sink or float on water? (Density of water = 1 g Cm^-3) body B having density 2520 kg m^-3

Which of the following will sink or float on water? (Density of water = 1 g Cm^-3)

 body C having density 1100 kg m^-3

Which of the following will sink or float on water? (Density of water = 1 g Cm^-3)

body D having density 0.85 g m^-3

What is the law of floatation?

The density of water is 1.0 g Cm^-3. The density of iron is 7.8 × 10″3 g Cm^-3. The density of mercury is 13.6 g Cm^-3.
Ans the following:
Will a piece of iron float or sink in water?

The density of water is 1.0 g Cm^-3. The density of iron is 7.8 × 10″3 g Cm^-3. The density of mercury is 13.6 g Cm^-3.
Answer the following:
Will a piece of iron float or sink in mercury?

The diagram given below show a body floating in three different liquids. A, B and C at different levels.
(a) In which liquid does the body experience the greatest buoyant force?
(b) Which liquid has the least density?
(c) Which liquid has the highest density?

For a floating body, how is its weight related to the buoyant force?

Why does a piece of ice float on water?

Explain why an iron needle sinks in water, but a ship made of iron floats on water.

State the energy changes that occur in a watch spring while it unwinds.

State the energy changes in the following while in use An electric bulb.

State the energy changes in the following while in use An electric oven.

State the energy changes in the following while in use A loudspeaker .

State the energy changes in the following while using a microphone.

State the energy changes in the following while using an electric motor.

When white light passes through a prism, it ............

The splitting of white light into its constituent colours is called .............

The speed of light in air or vacuum is

A ray of light moving from an optically rarer to a denser medium