
The equivalent gravitational force is ~

We know that ~

where,
= mass of 1st object = 500 kg
= mass of 2nd object = 20kg
- G = gravitational constant =

- r = distance between the objects = 2.12 m
Let's calculate the force ~
Answer:B.
Both increase as the mass and velocity increase.
John carry the heaviest load.
<h3>How to find out who is carrying the heavy load?</h3>
Write down given data from questions:
Board=510cm X 510mm.
Cylinder head with dimensions=43cm X 250mm.
Cylinder lies across the board 210cm from john.
Find out: Who is carry the heaviest load?
Calculation:
We assume that mass of cylinder head = x kg
Then weight=x x 9*81
W=9.81x Newton.
Weight per unit length= Weight/Total leanth
Weight per unit length= 9.81x/43
(w/l)=0.23x N/cm
From equation contition: 
(210+21.5)




Therefore 
To learn more about mass per unit length, refer to:
brainly.com/question/24180692
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1) 3 miles/Hour
The speed is defined as the distance covered divided by the time taken:

where
d = 1.5 mi is the distance
t = 0.5 h is the time taken
Substituting,

2) 1.34 m/s south
Velocity, instead, is a vector, so it has both a magnitude and a direction. We have:
is the displacement in meters
is the time taken in seconds
Substituting,

And the direction of the velocity is the same as the displacement, so it is south.