Helium and sound waves: Why your voice goes higher with helium.

Helium has an interesting effect on the voice, giving it a high-pitched quality, like donald duck. Assume that the voice is generated by the vocal cord vibrating above a gas filled tube open at one end. Explain why helium raises the frequency of the harmonics that characterise the voice.

Express physical quantities in different units of measurement.

1) A sphere has a radius 1.500m Find its volume in cm^3. Find its suface area in m^2 and in mm^2? 2) A truncated right circular cone has dimensions: upper base diameter =1.50cm lower base diameter = 4.00cm height = 6.00cm Find its volume in cm^3, m^3, mm^3 3) a person walks 5km in 1,5hr. What is the speed in mi ...continues

sound waves

A very large pipe is set up in a science museum. It is open at both ends, and it is large enough to walk inside it. A large loud speaker is set up at one end of the pipe. A student walks along the pipe and makes the following observations. While walking through the entire length of the pipe the student encountered 3 soft zones ...continues

Proper Units

What amount of heat is required to change 10 grams of Ice at -10 degrees Celsius into steam at 120 degrees Celsius?

Physics Problems Kinematics, Acceleration

Show all steps in computation. 1) A VW RAbbit can go from rest to 80.5 km/h (50.0 mi/h) in a modest 8.20 s. How long will it take to speed from 48.3 km/h to 64.4 km/h, along a straight run, if the average acceleration is the same as before? 2)During a takeoff a small plane has an average tangential acceleration of 5.0 m/s^2 ...continues

Rotational Equilibrium and Rotational Dynamics

The sailor in Figure P8.10 weighs 750N. The force F1 exerted by the wind on the sail is horizontal and acts through point B. The weight of the boat is 1250N and acts through point O, which is 0.8m from the point A along the line OA. The force F2 exerted by the water acts through point A. Determine the net force exerted by t ...continues

Physics Problems

Show all steps: What is the vertical component of the force the man exerts on the box? The man has his right foot on the top corner of the box at 53.1 degrees from the y axis, his left foot is stationary on the ground; the box is 400N. Newtons?_____ direction?______ 1)What is the horizontal component of the force exerte ...continues

Physics and career

my problem is how can physics help us in careers such us biotechnologist,astronomist,geology,biotechnology,aerospace,industry and communications?

Buoyant Forces

A bathysphere used for deep sea exploration has a radius of 1.5m and a mass of 1.2*10^4kg. In order to dive, this submarine takes on mass in the form of sea water. Determine the mass the submarine must take on so that it can descend at a constant speed of 1.2m/s, when the resistive force on it is 1100N upward. The density of ...continues

Buoyant Forces: Finding the horizontal area enclosed by the waterline of a ship.

Suppose one of the navy ships bobs up to float 11cm higher in the water when 50 fighters take off from it in 25 minutes, at a location where g=9.78m/s^2. Bristling with bombs and missiles, the planes have average mass 29000kg. Find the horizontal area enclosed by the waterline of the 4 billion dollar ship. By comparison, its ...continues