Newton's laws and forces Flashcards
1
Q
What is Newton’s first law?
A
A body will remain at a constant velocity unless acted upon by an external force
2
Q
What is Newton’s second law?
A
Force equals rate of change of momentum
3
Q
What is Newton’s third law?
A
To every action there is an equal and opposite reaction
4
Q
What is the contact force a combination of?
A
The normal reaction and a frictional force
5
Q
What is the maximal static friction force?
A
Max(Fs)= μsN
As this friction force is always equal to or less than
6
Q
What is the kinetic friction force?
A
Fk= μkN
7
Q
Which is typically larger μk or μs?
A
μs
8
Q
What is the gravitational force equation?
A
F_12=-(Gm_1 m_2)/r^2 r ̂
In the r hat direction
9
Q
What is Newton’s shell theorem?
A
- for any particle outside the shell, the shell acts as if all its mass is concentrated
in a point particle at the centre of the shell, - for any particle inside the shell, the gravitational force due to the shell precisely
cancels, i.e. it is zero.
