Both positive work and negative work have meaning: Positive work follows when the force has a component parallel to the displacement. Positive work adds energy to a system. Negative work follows when the force has a component opposite or against the displacement.
Gravity pulls objects down to the earth
Answer:
Explanation:
Given

Frictional Force is balanced by force due to car acceleration
Frictional force 




m = mass of the penny
r = distance of the penny from the center of the turntable or axis of rotation
w = angular speed of rotation of turntable
F = centripetal force experienced by the penny
centripetal force "F" experienced by the penny of "m" at distance "r" from axis of rotation is given as
F = m r w²
in the above equation , mass of penny "m" and angular speed "w" of the turntable is same at all places. hence the centripetal force directly depends on the radius .
hence greater the distance from center , greater will be the centripetal force to remain in place.
So at the edge of the turntable , the penny experiences largest centripetal force to remain in place.
Answer:
<h2>470.59 kg</h2>
Explanation:
The the mass of the car can be found by using the formula

f is the force
a is the acceleration
From the question we have

We have the final answer as
<h3>470.59 kg</h3>
Hope this helps you