Answer:
Explanation:
a ) The motion is one dimensional , so motion is along x - axis , starting from origin ( 0 , 0 )
b ) Initial velocity is 18.5 m /s when boat is situated at origin . When he displaces by 250 m along x axis and his position is ( 250 , 0 ) along x axis , his velocity becomes 36 m /s . Both his velocity and acceleration is along x - axis.
c ) Initial velocity vi = 18.5 m /s
final velocity vf = 36 m/s
Displacement x = 250 m
Acceleration a = ?
Most appropriate formula is given below .
vf² = vi² + 2 a x
2ax = vf² - vi²
x = ( vf² - vi² ) / 2 a
d )
Putting the given values
36² - 18.5² / 2 x 250
= 1296 - 342.25 / 500
= 1.9 m /s².
f ) Time interval t = ?
Required formula
vf = vi + at
t = (vf - vi ) / a
Putting the values
t = (30 - 18.5) / 1.9
= 6.05 second .
We simply use the formula,

Given, velocity = 4 m per s and distance = 120 m.
Substituting these values, we get
.
Thus, required time for the elevator in order to travel 120 m upwards is 30 s.
I think it's three days. I read it in assignment potion before but it's kinds fuzzy but I believe it's three days. Hopefully thats correct.
Answer:
12 neutrons
Explanation:
The number of protons also shows the atomic number. Therefore the element in question is Krypton (Kr), which also is a noble gas.
Neutrons = Mass number - protons - electrons
Here neutrons = 84 - 36 - 36 = 12
Answer:
Mass can never be negative. Everything has mass. Just like how they ask you to find area under the graph in maths. If the area is in the 3rd and 4th quadrant, when calculated, you would get negative answer.However, area can not be negative because it is a place/ location. It's exactly the same as mass.