Complete Question
A parallel plate capacitor creates a uniform electric field of 5 x 10^4 N/C and its plates are separated by 2 x 10^{-3}'m. A proton is placed at rest next to the positive plate and then released and moves toward the negative plate. When the proton arrives at the negative plate, what is its speed?
Answer:

Explanation:
From the question we are told that:
Electric field 
Distance 
At negative plate
Generally the equation for Velocity is mathematically given by

Therefore




dimension = 30.0 m ✕ 15.0 m ✕ 5.0 m.
density = 1.20 kg/m3
(a)volume = lenght * breadth * height
= 30 * 15 * 5
= 2250 metre cube = 2.25 cubic meter
(b) mass of air = density * volume
mass of air = 1.2 * 2250
mass of air = 2700kg
weight = mass * 9.8
= 2700 * 9.8
= 26,460 N
- The definition of Density is the amount of matter in a given space, or volume
- Density = mass/volume
- units for density kg/m^3
- Density of water 1g/ml
- Salt water is denser that is why don't sink as easily.
To know more about density visit : brainly.com/question/15164682
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The correct answer is:
Work is negative, the environment did work on the object, and the energy of the system decreases.
In fact, the work-energy theorem states that the work done by the system is equal to its variation of kinetic energy:

In this problem, the variation of kinetic energy
is negative (because the final velocity is less than the initial velocity), so the work is negative, and this means that the environment did work on the object, and its energy decreased.
Answer:
The shanghai maglev train is capable of reaching speeds of up to 217.48 in mph
217.48 mph
Explanation: