- 503 Views
- Uploaded on
- Presentation posted in: General

Newton’s Laws Of Motion

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Newton’s Laws Of Motion

Week

- Student will:
- Study the effects of forces on objects though
- Newton’s First Law of Motion
- Law of Inertia
- Newton’s Second Law
- Newton’s Third Law

- Study the effects of forces on objects though

- Questions
- What is Newton’s First Law Of Motion?

Newton’s First Law of Motion

- Law of Inertia
- Inertiameans “Tendency to resist change in motion”

- An object at rest, stays at rest. Object in motion, stays in motion unless acted upon by a force.

Net Force (Resultant force): Sum up all the forces

How do you know if an object is moving or not?

Part II: Analyzing The Event

Part II: Analyzing The Event

- Questions
- Newton’s 2nd Law is summarize with what formula?

Newton’s 2nd Law:

Net Force = Mass x Acceleration

Force is measured in Newton (N)

Mass is measured in kilograms (kg)

Acceleration is measured in (m/s2)

- How does friction help move you forward when walking?

Newton’s 3rd Law: For every action force, there is a reaction force of equalmagnitude (size), yet opposite in direction.

Forces ALWAYS come in pairs

- Bat hits ball/ball hits bat
- Push on wall/wall pushes back
- Falling object pulled by Earth/Earth pulled by falling object

- A bat hits a ball with a force of 50 N, what is the force of the ball on the bat?

- Example

A 20 Kg girl and a 40 Kg boy are on ice. The girl pushes a boy with a force of 20 N.What force must the girl experience?

- Is it possible to push someone harder than they push you?

Example: Newton’s Second Law

The Human Torch is pulling the Thing (not an easy feat) straight up off the ground by applying a force of 3000 N. What is the magnitude of the Thing’s acceleration? Assume The Thing’s mass is 224 kg.

- Steps
- Define

Given:

m= 224 kg

3000 N

9.8 m/s2

Unknown:

= ?

The Human Torch is pulling the Thing (not an easy feat) straight up off the ground by applying a force of 3000 N. What is the magnitude of the Thing’s acceleration? Assume The Thing’s mass is 224 kg.

- Think of ALL the forces that act upon an object

- Plan

Choose an equation or situation:

Rearrange the equation to isolate the unknown:

- Calculate

Substitute the values into the equation and solve

- Evaluate

The Thing is accelerating 3.593 m/s2upward.

Example: Newton Second Law

In order to travel, the Hulk has to leap from one place to another. Assuming his mass is 521.63 kg (1150 lbs), calculate the force that he exerts on the ground when he accelerates from 0 m/s to 391m/s (874.642 mph) in 0.8 seconds.

- Steps
- Define

Given:

m = 521.63 kg

= 0 m/s

= 391 m/s

t = 0.8 seconds

Unknown:

= ?

In order to travel, the Hulk has to leap from one place to another. Assuming his mass is 521.63 kg (1150 lbs), calculate the force that he exerts on the ground when he accelerates from 0 m/s to 391m/s (874.642 mph) in 0.8 seconds.

- Force needs magnitude and direction

- Plan

Choose an equation or situation:

Rearrange the equation to isolate the unknown:

- Calculate

Substitute the values into the equation and solve

254946.6625

254946.663 N

- Evaluate

The Force is positive, indicating an upward direction, and is a very large number (after all, it is the Hulk).

Through Newton’s Third Law of motion, the Hulk will need to exert a force of 291429.46 N to accelerate himself.