Wave Motion

The transverse waves can propagate through

• gases but not thorough metals
• metals but not through gases
• both gases and metals
• neither gases nor metals

In transverse waves, particles of the medium vibrate

• perpendicular to the direction of propagation of wave.
• parallel to the direction of propagation of waves
• at 30 degree with direction of propagation of waves
• at 45degree with direction of propagation of waves

Longitudinal waves can NOT travel through

• vacuum
• solids
• liquids
• gases

Longitudinal waves can NOT be

• reflected
• refracted
• interfered
• polarised

A 5.5 m length of string has a mass of 0.035 kg. If the tension in the string is 77 N, the speed of a wave on the string is

• 110 m s-1
• 165 m s-1
• 77 m s-1
• 102 m s-1

The speed of sound in humid air, as compared to that in dry air

• is same
• is less
• is more
• nothing can be said

Newton’s formula for the velocity of sound in gases is

• v = √P/ρ
• v= √ρ/P
• v = √ρ/2 P
• v = √2 P /ρ

An earthquake generates both transverse (S) and longitudinal (P) sound waves in the earth . The speed of S waves is about 4.5 km s-1 and that of P waves is about 8.0 km s-1 . A seismograph records P and S waves from an earthquake. The first P wave arrives 4.0 min before the first S wave . The epicentre of the earthquake is located at a distance of about :

• 25 Km
• 250 km
• 2,500 km
• 5,000 km

The ratio of velocity of sound in hydrogen gas (γ = 7/5 ) to helium gas (γ = 5/3 ) at same temperature is

• √21/5
• √42/ 5
• √7/ 5
• √34/ 5

Due to propagation longitudinal wave in a medium, the following quantities also propagate in the same direction

• Energy, momentum and mass
• Energy
• Energy and mass
• Energy and linear momentum