A boat's propeller has a rotational inertia of 4.0 kg · mº. After a constant torque is applied for 12 s, the rad

rad

propeller's angular speed changes from a clockwise 6.0 to a counterclockwise 6.0

S

S

What was the torque applied to the propeller?

the one with the highest speed

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

conservation of mass

mass before something happens = mass afterwards

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.