You can subtract the atomic number from the mass number in order to find the number of neutrons.
A=F/m
=5/12
=0.42 m/s^2
Since the ball stops, it decelerates at a rate of 0.42 m/s^2 before stopping and it’s final velocity is 0 m/s.
t=(u-v)/a
=(20-0)/0.42
=48 s
Answer:
7650 m.
Explanation:
Ocean floor depth, d is:
d = v * t,
where,
d = the distance from the vessel to the ocean floor (or the depth)
v = 1530 m/s = velocity of the ultrasonic sound
t = t_echo/2 = time that the ultrasonic sound needs to reach the ocean floor
t_echo = 10 s = time that the ultrasonic sound needs to reach the ocean floor and return back to the vessel.
d = v * t
= v * t_echo/2
= 1530 * 10/2
= 7650 m.