A50 kg skydiver is falling downwards and accelerating 6 m/s2 down. what is the net force on the skydiver?

300 n, up
8.3 n, down
300 n, down
500 n, up

Students in an introductory physics lab are performing an experiment with a parallel-plate capacitor made of two circular aluminum plates, each 11 cm in diameter, separated by 1.0 cm. how much charge can be added to each of the plates before a spark jumps between the two plates? for such flat electrodes, assume that value of 3×106n/c of the field causes a spark.

Aspring is used to stop a 50-kg package which is moving down a 20º incline. the spring has a constant k = 30 kn/m and is held by cables so that it is initially compressed 50 mm. knowing that the velocity of the package is 2 m/s when it is 8 m from the spring and neglecting friction, determine the maximum additional deformation of the spring in bringing the package to rest.

Which of the following is a measure of the amount of light a star directly emits?               a.  luminosity    b.  intensity    c.  wavelength    d.  brightness