1. if an external magnetic field increases in the area given, then the induced magnetic field points in
a) same direction
b) opposite direction
and the induced emf is
a) equal to zero
b) not equal to zero
2. if the external magnetic field is constant in the area given, then the induced magnetic field points in
a) same direction
b) opposite direction
and the induced emf is
a) equal to zero
b) not equal to zero
3. if an external magnetic field decreases in the area given, then the induced magnetic field points in
a) same direction
b) opposite direction
and the induced emf is
a) equal to zero
b) not equal to zero

Glass is transparent to visibile light under normal conditions; however, at extremely high intensities, glass will absorb most of the light incident upon it. this works through a process known as multiphoton absorption. in this process, several photons are absorbed at the same time. if very intense light whose photons carry 2ev of energy is shined onto a material with a band gap of 4ev, that light can be absorbed through two-photon absorption, because two photons have the right amount of energy to bridge the band gap. what is the minimum number of photons of 800-nm light that are needed to equal or exceed the band gap of fused silica glass

Point charges q1 = 51 µc and q2 = −27 µc are placed 1.0 m apart, with q2 on the right. what is the force (in n) on a third charge q3 = 19 µc placed midway between q1 and q2? (assume the positive direction is to the right. indicate the direction with the sign of your answer.)

What causes the formation of ocean currents?