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Astronauts on the ISS orbit Earth 16 times a day at a height of 400km above the surface. Given that the radius of Earth is approximately 6400km, how fast are the astronauts travelling?

v = 2𝜋R/T where R is the orbital radius, T is the time period.R = radius_of_earth + height_of_orbit = 6800km + 400km = 6800km = 6.8×10 6 m.T = hours_in_day/number_of_orbits_in_day = 24/16 hours = 1.5 hours =...
PV
Answered by Paaryn V. • Physics tutor
3087 Views

If an alpha particle (Z = 2) of kinetic energy 7 MeV is incident on a gold nucleus (Z = 79), what is its closest distance of approach?

In Rutherford Scattering, an incident particle will reach the closest distance of approach when it is on a collision course head on with the target nucleus. At the closest distance of approach, the alpha par...
RN
Answered by Robert N. • Physics tutor
5146 Views

Why cant I use the same expression for doppler effect when the source is in motion and when the listener is in motion?

This is a common misconception that involves changes in frames of reference. In most contexts moving towards an object refers to the same physical reality as the object moving towards you (at constant speed)...
FM
Answered by Francisco M. • Physics tutor
1489 Views

How are the momentum and kinetic energy of an object related?

The momentum of an object is given by p = m v, where p = momentum, m = mass of object and v = velocity.The kinetic energy of an object is given by KE = 1/2 * m v 2 where KE is the kinetic energy. Therefore t...
KC
Answered by Ketan C. • Physics tutor
2619 Views

What does the photoelectric effect demonstrate?

The dual nature of light. Sometimes it behaves as a particle, sometimes as a wave.
DM
Answered by Dario M. • Physics tutor
2068 Views