phy201

Seed question 11

Answer the following based on Newton's Second Law:

How much net force is required to accelerate a 12 kg mass at 3 m/s^2?

answer/question/discussion: ->->->->->->->->->->->-> :

m= 12kg

a=3 m/s^2

F= m * a

F= 12kg * 3 M/s^2

Fnet = 36newtons (kg m/s^2)

#$&*

What would be the acceleration of a 4 kg mass subject to a net force of 20 Newtons?

answer/question/discussion: ->->->->->->->->->->->-> :

Fnet = m * a

f= 20newtons

m = 4 kg

20newtons = 4 kg * a

a= 5m/s^2

#$&*

If you exert a force of 20 Newtons on a 10-kg object and it accelerates in the direction of your force at 1.5 m/s^2, then how do you know

there are other forces acting on the object besides your own?

answer/question/discussion: ->->->->->->->->->->->-> :

F= 20 newtons

m=10kg

a=1.5m/s^2

F=m * a

F= 10kg * 1.5 m/s^2

f=15 newtons

20newtons= 10kg + a

a= 2 m/s^2

You know that there are forces besides you own because if you are exerting a force of 20 newtons on an onject with a mass of 10kg the

acclereation should be 2m/s^2. But this object is going 1.5m/s^2 which is much faster. When calculated an object with a mass of 10kg only

needs a force of 15 newtons to accelerate at 1.5 m/s^2.

#$&*

What is the total of all those forces and in what direction does this total act?

answer/question/discussion: ->->->->->->->->->->->-> :

Fnet is 15 newtons of plus an additional 5 newtons to wqual 20 newtons total. The forces are acting in the direction that the object is

being forced, because it is going at a much faster rate, than needed.

#$&*

about 30 min