Laws of Motion
What is the equation associated with Newton's second law?
F = MA
force = mass*acceleration
what is the value of the acceleration due to gravity? Commonly shown as a small g
9.81 m/s^2
What is the force of gravity exerted on a 10 kg mass?
force of gravity = 98 Newtons
coefficient of friction on ice is less and that of pavement
The force of friction on pavement is greater
Are there more wheels or doors in the world?
Must support your argument
Newton's first law states that if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force.
Between what two values must the coefficient of friction (u) fall between?
0 to 1 (no units)
What is the net force if Lainey pushes a box to the left with 15 Newtons and Marc pushed the box to the right with 8 Newtons
7 Newtons to the left
A 10N horizontal force is applied to a 10kg box causing it to speed up. The force of kinetic friction is 5N. Describe the motion of the box
Will constantly accelerate as long as the force is applied
Does negative acceleration cause speed to decrease?
Not necessarily, depends on the orientation
If they are in-line velocity increases but opposite directions velocity decreases
No force is acting on the satellite
Fnet = 0 N
What is the equation to calculate the force of friction between objects?
Force of friction = u*m*g
of f = u*Normal
What is the acceleration of a 20 kg ball being pushed with a force of 100 Newtons
A car traveling 27m/s tops a hill. Model the hill as a portion of a circle with a radius of 250m. What is the centripetal acceleration of the car?
2.916 m/s^2 towards the center of the hill
In a vacuum, what falls faster, a brick or a feather?
Each fall the same speed
What does the third of Newton's laws state?
Newton's third law states that when two bodies interact, they apply forces to one another that are equal in magnitude and opposite in direction. The third law is also known as the law of action and reaction.
Centripetal acceleration can be solved for with this equation...
centripetal acceleration = (v^2)/r
In what direction does acceleration point as a car travels at a constant velocity around a circular corner?
To the center of the corner/circle
or
Perpendicular to the velocity vector.
A curve on an unbanked highway has a radius of 300 m. If the coefficient of friction is 0.6, what is the maximum velocity the car can be travelling?
42 m/s
Walk us through your process
What are the primary forces a space shuttle must overcome when leaving the atmosphere?
Drag and gravity
Apply two of Newton's laws to a hockey puck bouncing off a wall.
1st law- the force by the wall changed the direction of the puck (change in velocity)
2nd- the impulse force (F=m*a)
3rd- force on both the puck and wall.
How might we set up the equation to find the fastest speed a car is able to go around a corner?
*hint- two possible methods
vmax = square root of (u*g*r)
force of friction = m *(v^2/r)
Taylor (150 lbs.) and Josh (200 lbs.) are standing on frictionless ice. Taylor pushes on Josh. During the push which person exerts the greater force on the other?
They experience the same force, Newton's 3rd law
A curve on an unbanked highway has a radius of 200m. What minimum coefficient of static friction is required for a car to make the corner at 30 m/s
u = 0.46
justify your answer
What is the closest planet to the sun?
Mercury