A straight wire carrying 3.0 A current is laid in a E-W magnetic field. When 0.70 m of wire is in the field, the wire feels a force of 3.6 N. What is the strength of the magnetic field?

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?

Could we see a galaxy that is 20 billion light-years away?