Motion in a Straight Line — Physics STD 11 Science — Question

Does it matter if one uses gauge instead of absolute pressures in applying Bernoulli’s equation? Explain.

A barometer tube is 80cm long (above the mercury reservoir). It reads 76cm on a particular day. A small amount of water is introduced in the tube and the reading drops to 75.4cm. Find the relative humidity in the space above the mercury column if the saturation vapour pressure at the room temperature is 1.0cm.

Name the device used for measuring the mass of atoms and molecules.

Which of the following is the most precise device for measuring length :
(a) a vernier callipers with 20 divisions on the sliding scale
(b) a screw gauge of pitch 1 mm and 100 divisions on the circular scale
(c) an optical instrument that can measure length to within a wavelength of light?

If two waves of the same frequency but of different amplitudes travelling in opposite directions through a medium superpose upon each other, will they form stationary wave? Is energy transferred? Are there any nodes?

The minimum deviations suffered by red, yellow and violet beams passing through an equilateral transparent prism are 38.4°, 38.7° and 39.2° respectively. Calculate the dispersive power of the medium.

A person trying to lose weight (dieter) lifts a 10 kg mass, one thousand times, to a height of 0.5m each time. Assume that the potential energy lost each time she lowers the mass is dissipated. (a) How much work does she do against the gravitational force? (b) Fat supplies 3.8 × 10⁷J of energy per kilogram which is converted to mechanical energy with a 20% efficiency rate. How much fat will the dieter use up?

It is a common observation that rain clouds can be at about a kilometre altitude above the ground.
Estimate the time required to flatten the drop.

Why does a gas not have a unique value of specific heat?

If angular momentum is conserved in a system whose moment of inertia is decreased, will its rotational kinetic energy be also conserved? Explain.