In a supernova explosion, the iron core of a heavy star collapses to form a neutron star. assume the radius of the iron core of the star is rcore 3000 km, and the radius of the neutron star is rns 10 km. if the mass of the collapsing core is m - 1.4 msun (msun - 1 10su kg) and before the collapse the star completes a turn on its axis once every 30 days, a) what is the period of rotation of the neutron star after the collapse? , and b) what are the rotational kinetic energies before and after the collapse?

When using the scientist method, which step comes last?

Aforce of 8,480 n is applied to a cart to accelerate it at a rate of 26.5 m/s2. what is the mass of the cart? 865 kg 320 kg 12.1 kg 3.12 kg

The frequency of a tuning fork can be found by the method shown. a long tube open at both ends is submerged in a beaker of water, and the vibrating tuning fork is placed near the top of the tube. the length l of the air column is adjusted by moving the tube vertically. the sound waves generated by the fork are reinforced when the length of the air column corresponds to one of the resonant frequencies of the tube. the smallest value for l for which a peak occurs in sound intensity is 7 cm. l what is the frequency of the tuning fork? the speed of sound in air is 345 m/s. answer in units of hz