(English Medium) ICSE Class 9 - CISCE Question Bank Solutions for Physics

Why does nose start bleeding on high mountains?

What is an altimeter? State its principle. How is its scale calibrated?

What do the following indicate in a barometer regarding weather : gradual fall in the mercury level

What do the following indicate in a barometer regarding weather : sudden fall in the mercury level

What do the following indicate in a barometer regarding weather : Gradual rise in the mercury level?

The unit torr is related to the barometric height as :

The normal atmospheric pressure is : 

The atmospheric pressure at earth's surface is P₁ and inside mine is P₂. They are related as : 

At sea level, the atmospheric pressure is 1.04 x 10⁵ Pa. Assuming g = 10 m s^-2 and density of air to be uniform and equal to 1.3 kg m^-3, find the height of the atmosphere.

At sea level, the atmospheric pressure is 76 cm of Hg. If air pressure falls by 10 mm of Hg per 120m of ascent, what is the height of a hill where the barometer reads 70 cm Hg. State the assumption made by you.

Convert 1 mm of Hg into pascal. Take density of Hg = 13.6 x 10³ kg m^-3 and g = 9.8 m s^-2 .

At a given place, a mercury barometer records a pressure of 0.70 m of Hg. What would be the height of water column if mercury in barometer is replaced by water? Take density of mercury to be  = 13.6 × 10³ kg m^-3.

State the principle of floatation. 

A body is held immersed in a liquid. (i) Name the two forces acting on the body and draw a diagram to show these forces. (ii) State how the magnitudes of two forces mentioned in part (i) determine whether the body will float or sink in liquid when it is released. (iii) What is the net force on the body if it (a) sinks and (b) floats? 

When a piece of wood is suspended from the hook of a spring balance, it reads 70 gf. The wood is now lowered into water. What reading do you expect on the scale of spring balance?

A solid iron ball of mass 500 g is dropped in mercury contained in a beaker. (a) Will the ball float or sink? Give reasons. (b) What will be the apparent weight of the ball? 

Draw a diagram to show the forces acting on a body floating in water with its some part submerged. Name the forces and show their points of application. How is the weight of water displaced by the floating body related to the weight of the body itself?

A block of wood is so loaded that it just floats in water at room temperature. What change will occur in the state of floatation, if

(a) Some salt is added to water, (b) Water is heated?

Give reasons. 

A body of volume V and density ρ_s , floats with volume v inside a liquid of density ρ_L. Show that `"v"/V = ρ_s/ρ_L` .

Why is the floating ice less submerged in brine than in water?