• Support PF! Buy your school textbooks, materials and every day products Here!

Help with Newtons Second Law Question Please.

  • Thread starter 123tricks
  • Start date
  • #1
2
0

Homework Statement



Calculate the force needed to accelerate a 2.0kg ball at 3.0ms^2

(A) In space, a long way from Earth.
(B) On a frictionless horizontal surface, near the surface of the earth.
(C) vertically upward, near the surface of the earth.


Homework Equations



F = m*a

The Attempt at a Solution



(A) F = 2.0 * 3.0
F= 6N?

(B) Same as above?

(C) I am confused on this one.

Would it be F = m*a

F = 2.0 *(9.8 - 3.0)
F= 2.0 * 6.8
F= 13.6N?

or

F = 2.0 * 12.8 (To get from -9.8 to 3 = 12.8)
F= 24.8N

If those answers are wrong could anyone point me in the right direction as to what I am doing wrong?

Thanks.
 
Last edited:

Answers and Replies

  • #2
370
0
Edit: Aha, check your final line, you sure That 2 * 12.8 = 24.8? 0.o

First two are fine
 
  • #3
2
0
Edit: Aha, check your final line, you sure That 2 * 12.8 = 24.8? 0.o

First two are fine
Ahaha... I mean 25.6 :)
 
  • #4
370
0
thats right
 

Related Threads for: Help with Newtons Second Law Question Please.

Replies
2
Views
5K
Replies
3
Views
5K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
4
Views
4K
  • Last Post
Replies
13
Views
4K
  • Last Post
Replies
3
Views
4K
  • Last Post
Replies
9
Views
4K
Top