- OKAY. WE'RE NOW DOING MODULE 2, HOMEWORK PROBLEM 3.
AND THE PROBLEM READS:
WE HAVE 2 PARTICLES HAVE A MASS OF 8 KILOGRAMS
AND 12 KILOGRAMS RESPECTIVELY.
IF THEY'RE 800 MILLIMETERS APART,
DETERMINE THE FORCE OF GRAVITY ACTING BETWEEN THEM
AND COMPARE THIS RESULT WITH THE WEIGHT OF EACH PARTICLE.
OKAY. OUR EQUATION THEN IS FOR THE FORCE--
GRAVITATIONAL FORCE IS G TIMES M1 TIMES M2
DIVIDED BY THE DISTANCE BETWEEN THEM SQUARED.
SO FORCE THEN IS EQUAL TO G IS A GRAVITATIONAL CONSTANT,
66.73 TIMES 10 TO THE -12 METERS CUBED
DIVIDED BY A KILOGRAM SECOND SQUARED
TIMES MASS OF 1 IS 8 KILOGRAMS-- MASS OF 2 IS 12 KILOGRAMS
DIVIDED BY THE DISTANCE BETWEEN THEM,
WHICH IS .8 METERS SQUARED.
GRIND THAT ALL OUT, WE GET 10.0 TIMES 10 TO THE -9th NEWTONS,
OR YOU COULD SAY 10.0 NANONEWTONS.
OKAY. COMPARE THAT TO THE WEIGHTS.
WELL, THE WEIGHT OF 1 IS EQUAL TO--
WE HAVE 8 KILOGRAMS AS THE MASS TIMES THE ACCELERATION,
WHICH IS 9.81 METERS PER SECOND SQUARED
AND ENDS UP BEING 75.5 NEWTONS.
THE WEIGHT OF PARTICLE NUMBER 2 IS WE HAVE 12 KILOGRAMS
TIMES 9.81 METERS PER SECOND SQUARED,
THAT ONE IS 118 NEWTONS.
AND AS YOU CAN SEE, THE GRAVITATIONAL ATTRACTION
IS EXTREMELY SMALL COMPARE TO THE WEIGHTS. �