A negative lens with a focal length of -10.0 cm is on the same axis as a positive lens with a focal length of +20.0 cm as illustrated. The distance between the
lenses is 20.0 cm. A real object 3.00 cm high is placed 20.0 cm to the left of the
negative lens. After the light has passed through both lenses, the image is
- 20 cm to 20 cm -
a. 3.0 cm high and virtual.
b. 1.0 cm high and virtual.
c. 1.0 cm high and real.
d. 3.0 cm high and real.
e. None of these is correct.
I
Object

Which transition by an electron will release the greatest amount of energy? oa ob oc od

The uniform slender bar rests on a smooth horizon- tal surface when a force f is applied normal to the bar at point a. point a is observed to have an initial acceleration aa of 20 m/s2, and the bar has a corre- sponding angular acceleration of 18 rad /s2. deter- mine the distance b.

The ultracentrifuge is an important tool for separating and analyzing proteins. because of the enormous centripetal accelerations, the centrifuge must be carefully balanced, with each sample matched by a sample of identical mass on the opposite side. any difference in the masses of opposing samples creates a net force on the shaft of the rotor, potentially leading to a catastrophic failure of the apparatus. suppose a scientist makes a slight error in sample preparation and one sample has a mass 10 mg larger than the opposing sample. if the samples are 12 cm from the axis of the rotor and the ultracentrifuge spins at 70,000 rpm, what is the magnitude of the net force on the rotor due to the unbalanced samples? ( be thorough on your answer)