Q. The brakes are applied to a car traveling on a dry, level highway. A typical value for the magnitude of the car's acceleration is 5.45 m/s2. If the car's initial speed is 33 m/s, how long does it takes to stop and how far does it travel, starting from moment the brakes are applied?
Q. A small, plastic sphere of mass m = 123g is attached to a string. There is an electric field of 109N/C directed along the +x direction. If the string makes an angle θ = 30° with the y axis, what is the charge on sphere?