Try liters if you haven’t done it yet. I’m so sorry if i’m incorrect.
Given that:
Distance , s = 18.5 m
Velocity , v = 3.85 m/s
Time , t =?
Since,
Velocity = distance/time
or
Time= distance/velocity
time= 18.5/ 3.85
time= 4.8 s
So the time elapse between the release of the ball and the ball passing home plate is 4.8 seconds.
Answer:
2.068 x 10^6 m / s
Explanation:
radius, r = 5.92 x 10^-11 m
mass of electron, m = 9.1 x 10^-31 kg
charge of electron, q = 1.6 x 10^-19 C
As the electron is revolving in a circular path, it experiences a centripetal force which is balanced by the electrostatic force between the electron and the nucleus.
centripetal force = 
Electrostatic force = 
where, k be the Coulombic constant, k = 9 x 10^9 Nm^2 / C^2
So, balancing both the forces we get



v = 2.068 x 10^6 m / s
Thus, the speed of the electron is give by 2.068 x 10^6 m / s.
Average speed = (total distance covered) / (time to cover the distance)
Total distance = (77km + 66km) = 143 kilometers
Time to cover the distance = 2 hours
Average speed = (143 km) / (2 hours) = 71.5 km per hour