Explanation:
When Joe works alone, the total number of words he typed can be given by:
Total words = (40 words per minute) x (60 minutes per hour) x (2.5 hours)
Total words = 6000 words
Now, when Joe and Mark work together, let 'y' be the number of hours for which they both work simultaneously:
Total words = Words Typed by Joe + Words Typed by Mark
6000 = {(40 words per minute) x (60 minutes per hours) x (y hours)} + {(20 words per minute) x (60 minutes per hours) x (y hours)}
6000 = 2400y + 1200y = 3600y
y = 1.67 hours = 1 hour and 40 minutes
Thus, working together simultaneously, Joe and Mark will take 1 hour and 40 minutes to complete the report.
To solve this problem we will apply the concepts related to Newton's second law that relates force as the product between acceleration and mass. From there, we will get the acceleration. Finally, through the cinematic equations of motion we will find the time required by the object.
If the Force (F) is 42N on an object of mass (m) of 83000kg we have that the acceleration would be by Newton's second law.

Replacing,


The total speed change
we have that the value is 0.71m/s
If we know that acceleration is the change of speed in a fraction of time,

We have that,


Therefore the Rocket should be fired around to 1403.16s
In linear motion , when a body moves with uniform velocity , in time t , its linear displacement will be ;
S = r∅ S = vt
r∅ = vt
r.∅ / t = v
As
v = rw
where ∅ = 90° is the angle between between radius vector r and angular velocity w (omega )
In case ∅ ≠ 90° , we can write v = r w sin∅
It gives us v = w× r