Statics and dynamics

Question 1

What is the formula of force and what is the SI unit?

Answer 1

F= m * a (newton)

Question 2

What is newtons first law (of inertia?)

Answer 2

An object either remains at rest or continues to move linearly at a constant velocity, unless acted upon a net force.

Question 3

What is newtons second law (of dynamics?)

Answer 3

The acceleration of an object and the force acting on the object are proportional to each other.

F= m * a.

Question 4

What is newtons third law of dynamics?

Answer 4

Describes the symmetry of interaction: when object A exerts a force on object B, then object B exerts a force on object A with equal magnitude but in the opposite direction.

Question 5

What is the law of universal gravitation?

What is the formula?

Answer 5

A particle attracts every particle in the universe with a force that is directly proportional to the product of their masses

Or

A particle attract every particle in the universe with a force that is inversely proportional to the square of the distance (r) between them.

F= G * (m1 * m2)/r2

Question 6

Hooke’s law?

Answer 6

If a spring is extended, then a restoring force develops which is proportional to the extension (s):

F= -k * s

K is a spring constant: N/m

Question 7

What is friction?

How do we solve the formula

Answer 7

Counter force.

F = W/s

Question 8

What should the net force be on an object for the object to be in equilibrium?

Answer 8

Zero.

Question 9

What does inertia mean?

Answer 9

Resistance to change in velocity .

Question 10

What is Newtons third law?

Answer 10

Symmetry of interaction.

Question 11

When is an object in equilibrium?

Answer 11

If the net force acting on it is zero.

Question 12

What is the constant (G) in gravitational force?`

Answer 12

6.67 10 -11 m3/kgs2