a 15kg child is riding a merry go round at 3rpm. what centripetal force must she exert if she is 8m from the center

This is another application of Newton's second law of motion

Force = (mass) x (acceleration).

The quantities are a little more complicated in circular motion than
they are in plain old straight-line motion.  In circular motion, the 'force'
is the centripetal force on the object, always pointing toward the center
of the circle.  And the 'acceleration' is the centripetal acceleration, also
pointing toward the center of the circle, and equal to

The only thing we really need to find is the centripetal acceleration, and
then we'll have everything needed to plug into the formula and calculate
the centripetal force.

Speed = (distance) / (time) =

(3 circumferences) / (minute) =

(3 x 2pi x radius) / minute =

(6 pi x 8 meters) / (60 sec) =  0.8 pi m/s .

Acceleration = (speed)² / (radius) =

0.64 pi²  m²/s²  /  (8 meters) = 0.08 pi²  m/s²  =

0.79 m/s² (rounded) .

Force = (mass) x (acceleration) =

(15 kg) x (0.79 m/s²)  =  11.84 newtons

I would not say that she "exerts this centripetal force".  The fact of
the matter is much simpler:  This is the force that something must
exert on her, pointing toward the center, in order to keep her revolving
around the center at that speed.  It could be the friction between her
shoes and the platform, if she's standing on the merry-go-round.
It could be a rope tied between her ankle and something at the center
of the rotating platform.  It could be the safety belt on the horse that
she's riding.  Whatever it is, something has to constantly pull her toward
the center of the platform, with a force of 11.84 newtons, otherwise her
15kg body will not travel in that circular path.

Related Questions

Form of communication that reaches large audiences without personal contact.

Socialization is the process of internalization of the norms and ideologies of society by an individual. It encompasses learning and teaching to attain social and cultural continuity. It also has various forms. One of which is the MASS MEDIUM/MEDIA which is a form of communication that does not need personal contact to relay or convey and information. Examples of which are books, films, internet, magazines and so forth.

The form of communication that doesn't require personal contact and capable of getting to a large audience is referred to as mass media.

What is Communication?

This is the process in which information is transferred from one person to another.

Mass media which comprises of newspapers, internet etc reach large audiences without personal contact and is the commonest means in these present day.

A factor that influences your resting metabolic rate is

Gender....................

ITS GENDER

Explanation:

MEN TEND TO HAVE A FASTER METABOLISM DUE TO HORMONAL CHANGES.

Micah knows that a car had a change in velocity of 15 m/s. To determine acceleration, Micah also needs the_______________ of the total trip in seconds.

Duration of the total trip

Explanation:

Acceleration is defined as the rate of change of velocity of an object:

where

is the change in velocity

is the duration of the change in velocity

Acceleration is measured in meters per squared seconds, . Also, we should note that acceleration is a vector quantity, so in order to completely define acceleration we also need to specify the direction.