Dynamic and Statics

Question 1

Newton’s first law of motion is defined as

Answer 1

Inertia, and object in motion will stay in motion and an object at rest will stay at rest if the net outside force is zero

Question 2

Newton’s second law of motion is defined as

Answer 2

Net force= Mass * acceleration

Question 3

Newton’s third law of motion is defined as

Answer 3

An object that acts on another object with Force A will receive an equal and opposite reaction force from that object Force B

Question 4

What is friction
The equation?

Answer 4

Friction is define by mew * normal force where mew is the friction constant
Friction opposes motion

Question 5

what is static friction

Answer 5

It is the friction that is equal to the applied force that keeps the object at rest

Question 6

What is kinetic friction

Answer 6

It is the friction that opposes movement, to calculate it you would use the equation.

Question 7

What does it mean to be in mechanical equilibrium

Answer 7

To be in mechanical equilibrium the net force in the x and y have to be zero and the net rotational force has to be zero

Question 8

What is the force of gravity on a ramp equivalent to

Answer 8

mgsintheta

Question 9

What is the net force on an object sliding down a ramp with friction? Without friction?

Answer 9

friction, -mgsintheta+Friction
Without friction, -mgsintheta

Question 10

What is the net force on an object sliding up a ramp with friction vs without friction

Answer 10

Friction: -mgsintheta-friction
Without: -mgsintheta

Question 11

What is torque
what direction is torque negative? Positive?

Answer 11

Torque is the tendency of a force to cause rotational motion
Clockwise is negative, counter-clockwise is positive

Question 12

What is the equation for torque

Answer 12

T= r F sin theta
T= r F perpendicular

Question 13

On the left side of a seesaw a block with mass A sits on seat A. The plank of the seesaw is length L and the pivot point length M away from seat A which is closer. (pivot point is closer to seat A). Seat B is length N away from the pivot point.
M<N
How would you solve to problem to find how much mass B must be so that the seesaw is balanced.

Answer 13

When it is balance T=0
Set the point of reference at the pivot point
0= -M * MassA(9.8) + N * MassB(9.8)

Question 14

Apply F= Ma
If an object is moving at a constant velocity, what is the net force? Why is this so?

Answer 14

The net force=0
Moving at constant velocity means there is zero acceleration.