A magnetar is a rare type of rotating neutron star with one…

A magnetar is a rare type of rotating neutron star with one of the most powerful magnetic fields in the universe. On March 12, 2020, a magnetar called Swift J1818.0–1607 was discovered in our own Milky Way galaxy, and it is the fastest spinning magnetar ever discovered, spinning at a rate of once every 1.4 seconds!  It’s a spherical object with a mass twice that of the Sun (mass of Sun is 1.99 x 1030kg), but with a diameter less than 20 miles (about 30 km)!  Suppose a mysterious force was exerted tangent to the star at it’s equator, causing the rate of spin to slow down to once every 24 hours (like Earth), and suppose it took 1 year (31,557,600 seconds) for this change to take place. a. How much force would be required to cause this change? b. How much torque would be required? c. What would its angular acceleration be? Express this in SI units.

A soldier is standing on top of a building, 13.5 m above the…

A soldier is standing on top of a building, 13.5 m above the ground. He tosses a 4.6 kg hand grenade straight up at 5.6 m/s, trying to hit an enemy helicopter that is flying overhead. He misses, and the grenade falls toward the ground. If air resistance is negligible, how fast is the grenade moving when it is 1.2 m above the ground? YOU MUST USE ENERGY CONCEPTS/EQUATIONS TO SOLVE. YOU WILL NOT RECEIVE FULL CREDIT IF YOU SOLVE IT OTHER WAYS.