Question

***I only need the second question***
During World War I, the Germans had a gun
called Big Bertha that was used to shell Paris.
The shell had an initial speed of 2.41 km/s at
an initial inclination of 61.5 to the horizontal.
The acceleration of gravity is 9.8 m/s2 .
How far away did the shell hit?
Answer in units of km


How long was it in the air?
Answer in units of s

Answer 1

hi,

hence u r confident with the 1st one I think u don't need much of an explanation for the 2nd one

before all let's just convert Km/s into m/s
2.41 km/s = 2410m/s
To solve the second part
First we have to find Vy
Vy = 2410 m/s * sin 61.5
= 2410 m/s * 0.8788
=2117.908 m/s

When the shell reaches it's maximum height the vertical velocity component will be zero

based on that theorem let's apply linear motion equation
V = u + at
0 = 2117.908 m/s - 9.8 m/S^2 * (t)
t = 216.1130 s

As the shell has to go upward and comes back to earth the shell will require a same amount of time in order to reach earth again so the total time that shell will spend on the air will be
2*t
= 432.226 s

I think this should be the answer (though they are in decimal values )
hope this will help ya!!!