What is the magnitude of the maximum velocity that a 0.3–kilogram mass attached to a 0.75–meter string can have if the mass is whirled around in a circular horizontal path? The maximum tension that the string can withstand is 250 newtons.

An object resting on a table weighs 100 n. with what force is the object pushing on the table? with what force is the table pushing on the object? explain how you got your answer.

An electron moves with a constant horizontal velocity of 3.0 × 106 m/s and no initial vertical velocity as it enters a deflector inside a tv tube. the electron strikes the screen after traveling 26 cm horizontally and 19 cm vertically upward with no horizontal acceleration. what is the constant vertical acceleration provided by the deflector? (the effects of gravity can be ignored.)

The electric field inside a cell membrane is 8.0mn/c. what's the force on a singly charged ion in this field?