A small 2.05-g plastic ball that has a charge q of 1.75 C is suspended by a string that has a length L of 1.00 m in a uniform electric field, as shown in the figure. If the ball is in equilibrium when the string makes a 9.80 Solution Balancing vertical forces, Tcos?=mg Balancing horizontal forces, qE=TSin? Dividing both equations, Tan ?=qE/mg q=mgTan?/E=0.0025*9.81*Tan 15.5/1000=6.80?C .
A small 2.05-g plastic ball that has a charge q of 1.75 C is suspended by a string that has a length L of 1.00 m in a uniform electric field, as shown in the figure. If the ball is in equilibrium when the string makes a 9.80 Solution Balancing vertical forces, Tcos?=mg Balancing horizontal forces, qE=TSin? Dividing both equations, Tan ?=qE/mg q=mgTan?/E=0.0025*9.81*Tan 15.5/1000=6.80?C .