Anegative charged particle of known magnitude q is placed in a uniform electric field of known strength e. what additional information is needed to determine the magnitude of the force on the particle?

a. the distance between the charged plates producing the uniform field.
b. the distance from the nearest plate to the charged particle.
c. the magnitude of the charges producing the field.
d. the mass of the negatively charged particle.
d. no additional information is needed.

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?