Take a moment to understand this apparatus: Current passes through a rigid copper conductor mounted to a wood plate. The wood plate is mounted on a scale which measures the downward force exerted on the conductor. The scale is adjusted to read zero when no current flows. A magnet is placed next to the conductor, on a stand that is separate from the scale. When current flows through the conductor, the the interaction with the magnetic field causes a downward force on the conductor, which we can read on the scale. Which force is measured by the scale

Ahonda civic travels in a straight line along a road. its distance x from a stop sign is given as a function of time t by the equation x(t)= î± t2â î² t3, where î± = 1.53 m/s2 and î² = 5.50ã10â2 m/s3 .

22. the effect of threshold braking is to a cause skids. b. lock wheels. c. prevent locking of wheels. d. increase stopping distance.

The particle in a two-dimensional well is a useful model for the motion of electrons around the indole ring (3), the conjugated cycle found in the side chain of tryptophan. we may regard indole as a rectangle with sides of length 280 pm and 450 pm, with 10 electrons in the conjugated p system. as in case study 9.1, we assume that in the ground state of the molecule each quantized level is occupied by two electrons. (a) calculate the energy of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels. 9.27 electrons around the porphine ring (4), the conjugated macrocycle that forms the structural basis of the heme group and the chlorophylls. we may treat the group as a circular ring of radius 440 pm, with 20 electrons in the conjugated system moving along the perimeter of the ring. as in exercise 9.26, assume that in the ground state of the molecule quantized each level is occupied by two electrons. (a) calculate the energy and angular momentum of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels.