PUC Science कक्षा ११ - Karnataka Board PUC Question Bank Solutions for Physics

A steel wire of mass 4⋅0 g and length 80 cm is fixed at the two ends. The tension in the wire is 50 N. Find the frequency and wavelength of the fourth harmonic of the fundamental.

A wire, fixed at both ends is seen to vibrate at a resonant frequency of 240 Hz and also at 320 Hz. (a) What could be the maximum value of the fundamental frequency? (b) If transverse waves can travel on this string at a speed of 40 m s⁻¹, what is its length?

A 660 Hz tuning fork sets up vibration in a string clamped at both ends. The wave speed for a transverse wave on this string is 220 m s⁻¹ and the string vibrates in three loops. (a) Find the length of the string. (b) If the maximum amplitude of a particle is 0⋅5 cm, write a suitable equation describing the motion.

Three resonant frequencies of a string are 90, 150 and 210 Hz. (a) Find the highest possible fundamental frequency of vibration of this string. (b) Which harmonics of the fundamental are the given frequencies? (c) Which overtones are these frequencies? (d) If the length of the string is 80 cm, what would be the speed of a transverse wave on this string?

Water flows through a horizontal tube of variable cross section. The area of cross section at A and B are 4 mm² and 2 mm² respectively. If 1 cc of water enters per second through A, find (a) the speed of water at A, (b) the speed of water at B and (c) the pressure difference P_A − P_B.

The equation of a standing wave, produced on a string fixed at both ends, is
\[y = \left( 0 \cdot 4  cm \right)  \sin  \left[ \left( 0 \cdot 314  {cm}^{- 1} \right)  x \right]  \cos  \left[ \left( 600\pi  s^{- 1} \right)  t \right]\]
What could be the smallest length of the string?

The phenomenon of beats can take place

Does the temperature of a body depend on the frame from which it is observed?

It is said that mercury is used in defining the temperature scale because it expands uniformly with  temperature. If the temperature scale is not yet defined, is it logical to say that a substance expands uniformly with temperature?

Can the bulb of a thermometer be made of an adiabatic wall?

Why do marine animals live deep inside a lake when the surface of the lake freezes?

The length of a brass rod is found to be less on a hot summer day than on a cold winter day as measured by the same aluminium scale. Can we conclude that brass shrinks on heating?

The density of water at 4°C is supposed to be 1000 kg m^–3. Is it same at sea level and at high altitude?

A spherical shell is heated. The volume changes according to the equation V_θ = V₀ (1 + γ^θ). Does the volume refer to the volume enclosed by the shell or the volume of the material making up the shell?

Which of the curves in the following figure represents the relation between Celsius and Fahrenheit temperatures?

Which of the following pairs may give equal numerical values of the temperature of a body?

If the temperature of a uniform rod is slightly increased by ∆t, its moment of inertia I about a line parallel to itself will increase by

The temperature of water at the surface of a deep lake is 2°C. The temperature expected at the bottom is

An aluminium sphere is dipped into water at 10°C. If the temperature is increased, the force of buoyancy

A spinning wheel is brought in contact with an identical wheel spinning at identical speed. The wheels slow down under the action of friction. Which of the following energies of the first wheel decreases?

(a) Kinetic
(b) Total
(c) Mechanical
(d) Internal