The electrostatic force between two positive point charges is f when the charges are 0.1 meter apart. when these point charges are placed 0.05 meter apart, the electrostatic force between them
a) a f and repelling
b) 1/4f and repelling
c) 4f and attracting
d) 1/4f and attracting

*if you could tell me how you got this answer that would be great as i'm very lost on this one

Akg a of 55 m at an of 11 ? . if is at 98 km/h,be ?

Agas initially at p1 = 1 bar and occupying a volume of 0.5 liter is compressed within a piston–cylinder assembly to a final pressure p2 = 4 bar. (a) if the relationship between pressure and volume during the compression is pv = constant, determine the volume, in liters, at a pressure of 3 bar. (b) repeat for a linear pressure–volume relationship between the same end states. reference

An athlete swings a ball, connected to the end of a chain, in a horizontal circle. the athlete is able to rotate the ball at the rate of 8.13 rev/s when the length of the chain is 0.600 m. when he increases the length to 0.900 m, he is able to rotate the ball only 6.04 rev/s. (a) which rate of rotation gives the greater speed for the ball? 6.04 rev/s 8.13 rev/s (b) what is the centripetal acceleration of the ball at 8.13 rev/s? m/s2 (c) what is the centripetal acceleration at 6.04 rev/s? m/s2