On planet tehar, the free-fall acceleration is the same as that on earth, but there is also a strong downward electric field that is uniform close to the planet's surface. a 1.84-kg ball having a charge of 5.28 μc is thrown upward at a speed of 20.1 m/s. it hits the ground after an interval of 4.10 s. what is the potential difference between the starting point and the top point of the trajectory? (use 9.8 m/s^2 for the acceleration due to gravity.)

The potential difference between the starting point and the top of the trajectory is 82.51V

Explanation:

Finding acceleration of the ball

Using kinematics we can find the acceleration of the ball.

At the top of the trajectory we have vertical velocity v = 0 and the time is half of the total time

Electric field potential difference

We can obtain the potential difference from the electric field and the distance between the starting point and the top of the trajectory by using the following equation:

d being the distance from the surface to the top of the trajectory of the ball.

With the given values, we can find the sum of the gravitational and electric forces on the object in order to obtain the electric field on the surface of the planet.

We start with:

Now we can calculate d using kinematics and the fact that  and at the top of the trajectory.

The last step is to use V = E/d to find the final

The potential difference between the starting point and the top of the trajectory is 82.51V

this would be about 43%