11.

A metro train starts from rest and in 5 s achieves 108 km/h. After that it moves with constant velocity and comes to rest after travelling 45 m with uniform retardation. If total distance travelled is 395 m, find total time of travelling.

• 12.2 s

• 15.3 s

• 9 s

• 17.2 s

A tuning fork A produces 4 beats/s with another tuning fork B of frequency 320 Hz. On filing one of the prongs of A, 4 beats/s are again heard when sounded with the same fork B. Then, the frequency of the fork A before filing is

• 328 Hz

• 316 Hz

• 324 Hz

• 320 Hz

If there were no gravity, which of the following will not be there for a fluid?

• Viscosity

• Surface tension

• Pressure

• Archimedes' upward thrust

In Young's double slit experiment with sodium vapour lamp of wavelength 589 nm and the slits 0.589 mm apart, the half angular width of the central maximum is

• sin^-1 (0.01)

• sin^-1 (0.0001)

• sin^-1 (0.001)

• sin^-1 (0.1)

In Carnot engine efficiency is 40% at hot reservoir temperature T.  For efficiency 50%,  what will be temperature of hot reservoir?

• $\frac{\mathrm{T}}{5}$

• $\frac{2 \mathrm{T}}{5}$

• 6 T

• $\frac{6\mathrm{T}}{5}$

Which one of the following statements is true?

• Both light and sound waves in air are transverse

• The sound waves in air are longitudinal while the light waves are transverse

• Both light and sound waves in air are longitudinal

• Both light and sound waves can travel in vacuum

A closed organ pipe of length 20 cm is sounded with tuning fork in resonance. What is frequency of tuning fork? (v = 332 m/s)

• 300 Hz

• 350 Hz

• 375 Hz

• 415 Hz

The temperature of the sun can be found out by using

• Wien's displacement law

• Kepler's law of motion

• Stefan's Boltzmann law

• Planck's law

Pressure of an ideal gas is increased by keeping temperature constant. What is effect on kinetic energy of molecules?

• Increase

• Decrease

• No change

• Cannot be determined

A transverse wave is expressed as, $\mathrm{y} = {\mathrm{y}}_{\mathrm{o}} \sin 2\mathrm{\pi f} \mathrm{t}$  For what value of λ, maximum particle velocity equals to 4 times the wave velocity?

• ${\mathrm{y}}_{\mathrm{o}} \frac{\mathrm{\pi }}{2}$

• $2 {\mathrm{y}}_{\mathrm{o}} \mathrm{\pi }$

• ${\mathrm{y}}_{\mathrm{o}} \mathrm{\pi }$

• ${\mathrm{y}}_{\mathrm{o}} \frac{\mathrm{\pi }}{4}$