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why does applying the brakes of a car cause the temperature of the breaks to increase?

The increase in heat is caused by friction between the brakes and the wheels. This work done between the brakes and the wheels, causes a decrease in kinetic energy ...

Answered by Hugo H. • Physics tutor

11929 Views

What path would a charge moving in the x-y plane track, in the presence of a uniform magnetic field out of the page?

The magnetic force on a moving charge is always perpendicular to the directions of both velocity and B-field vectors. This means that in the presence of a uniform magnetic field, a particle will experienc...

Answered by Arsenios H. • Physics tutor

1476 Views

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 = 6.8×10⁶m.T = hours_in_day/number_of_orbits_in_day = 24/16 hours =...

Answered by Paaryn V. • Physics tutor

1775 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 ...

Answered by Robert N. • Physics tutor

3595 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 spe...

Answered by Francisco M. • Physics tutor

1029 Views