Other Physics Answers

1.    The diameter of a hydrogen atom is 1.0E-10 m (i.e. 1.0E-10 m/atom). How many hydrogen atoms could fit along a 1.0 cm line?

(number = length/(unit length))

2.    Earth travels with a speed of 30 km/s around the sun. What is the circumference of Earth’s orbit (which takes one year to travel)?

(distance = speed * time)

3.    A light-year is the distance light travels in one year, traveling with a speed of 3.0E8 m/s. How far is that in meters? (distance = speed * time)

4.    The wavelength of an ultrasound wave is 3.0E-4 m (i.e. 3.0E-4 m/wavelength). How many wavelengths would fit in a layer of skin with thickness 2.0 mm?

(number = length/(unit length))

A gymnasium is 16 m high. By what percent is the air pressure at the floor greater than the air pressure at the ceiling? Assume that pressure at the bottom is 1 atm and the density of air stays constant. The density of air is 1.29 kg/m³

a disc of 8cm radius rotate horizontally with angular velocity 120 revolution per second. Suddenly a small particle drop onto the edge of disc. The angular velocity of the disc reduce to 85 revolution per second. Calculate the mass of small particles if moment inertia of the disc is 6x10^-4 kgm²

A man falls 5m from a ladder . How long will take him to hit the ground ? g=10m/s^2

A pilot is preparing his private jet for a short trip. During take-off, the sound intensity level of a jet engine is 140 dB at a distance of 30 m. What is the sound intensity level at a distance of 1.0 km?

A pilot is preparing his private jet for a short trip. During take-off, the sound intensity level of a jet engine is 140 dB at a distance of 30 m. What is the sound intensity level at a distance of 1.0 km?