newton’s laws

17
Bellwork 2/2/2011 A penny dropped into a wishing well reaches the bottom in 1.50 seconds. What was the velocity at impact? In a bizarre but harmless accident, Superman fell from the top of the Eiffel Tower. How fast was Superman traveling when he hit the ground 7.8 seconds after

Upload: c-meador

Post on 17-May-2015

1.677 views

Category:

Education


8 download

TRANSCRIPT

  • 1. Bellwork 2/2/2011
    A penny dropped into a wishing well reaches the bottom in 1.50 seconds. What was the velocity at impact?
    In a bizarre but harmless accident, Superman fell from the top of the Eiffel Tower. How fast was Superman
    traveling when he hit the ground 7.8 seconds after falling?

2. 1. Who proposed the law of motion that for every action there is an equal and opposite reaction? A. Albert Einstein B. Isaac Newton C. Galileo
2. Which branch of science deals with the study of motion, forces, & energy? A. Physics B. Chemistry C. Astronomy
3. Which law of motion states, An object in motion will remain in motion and an object at rest will remain at rest unless acted upon by an unbalanced force? A. 1st Law B. 2nd Law C. 3rd Law
4. Which is the correct way to calculate the speed of an object? A. Distance multiplied by time B. Distance divided by time C. Time divided by distance
3. Newtons Laws
4. What makes an object speed up, slow down or change directions?
What determines how much an object speeds up or slows down
5. Newtons first-Law of Inertia
Inertia-the tendency of an object to resist a change in motion unless an outside force acts on the object
In other words-things that are still want to stay still.
6. Everything resists changes in motion.
Small things can accelerate with a small force
Larger things take larger forces to move them.
7. Newtons 1st
An object at rest remains at rest and an object in motion maintains its velocity (speed in a particular direction) unless it experiences a net force (unbalanced force, outside force)
8. Newtons 2nd
The unbalanced force acting on an object equals the objects mass times its acceleration
F=ma
Net force = mass * acceleration
9. More mass= smaller acceleration
Less mass = bigger acceleration
Force is measured in newtons
1N = 1 kg * 1 m/s2
10. We can rearrange the formula to solve for any of the variables.
11. Video
Brain Pop
12. Bellwork!!!2/1/2011
Write down two examples of each of Newtons three laws.
Newtons 1st
Newtons 2nd
Newtons 3rd
Video
13. Gravity
Force on an object due to gravity = weight
On Earth, your weight is simply the amount of gravitational force exerted on you by the Earth.
Weight = mass * free fall acceleration
W=mg
Weight is measured in Newtons (because it is a force)
14. Free fall-when Earths gravity is theonly force acting on an object
Satellites and the space station are in constant free fall.
When air resistance and weight are equal-objects meet terminal velocity.
Projectile Motion=the curved path followed by an object that is thrown, launched, or otherwise projected near the surface of Earth.
15. Newtons 3rd Law-For every action there is an equal and opposite reaction
16. Conservation of Momentum
The total momentum of two or more objects after they collide is the same as it was before the collision.
17. Momentum-product of the mass and velocity of an object
P=mv