course phy 121
Seed quest 11.1Answer 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:
Fnet = m*a
Fnet = 12kg * 3m/s^2
Fnet = 36N
What would be the acceleration of a 4 kg mass subject to a net force of 20 Newtons?
answer/question/discussion:
a= Fnet/m
a= 20N/4kg = 20 kg * m/s^2
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:
Two ways. You can figure what the acceleration should be if the only force acting on it is the 20N.
20N/10kg = 2 m/s^2
This is higher than the actual acceleration of the object so you know something has decreased the net force.
You can also figure out what the net force on the object is that accelerates a 10kg object to 1.5m/s^2
10kg*1.5m/s^2 = 15N
What is the total of all those forces and in what direction does this total act?
answer/question/discussion:
Fnet = m*a
Fnet = 10kg * 1.5 m/s^2 = 15 N
The total force acts in the direction of the movement, however the force that decreased the net force from 20 to 15 is acting against the movement.
&#Very good responses. Let me know if you have questions. &#