An electron of mass 9.11×10-31kg leaves one end of a tv picture tube with zero initial speed and travels in a straight line to the accelerating grid, which is a distance 1.30cm away. it reaches the grid with a speed of 2.50×106m/s . the accelerating force is constant.
a)find the acceleration.
b)find the time to reach the grid.
c)find the net force. (you can ignore the gravitational force on the electron).

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?