Friction
Why do soccer players or football players wear cleats?
They wear them with spikes to increase friction so they don't slip or fall.
What is Newtons first law?
An object in motion will remain in motion in the same direction unless acted upon by an outside force; an object at rest will remain at rest unless acted upon by an outside force. Once it is in motion, it will continue in motion in the same direction.
Does gravity affect time?
No.
What is motion?
A change in position compared to a reference point.
If an object is in free fall, what is the only force acting upon it?
Gravity and air resistance.
Define friction?
Friction is the force that opposes the relative motion between the two surfaces of objects in contact. The force of friction always acts in the direction opposite to that of the applied force.
Which type of Newtons law is this example?
1. A passenger gets flown forward when the car hits the wall.
First Law
What planet has the strongest gravitational pull?
The Sun.
What is speed?
How fast an object changes its position;rate.
What unit is used to measure forces?
Newton's.
What is the cause of friction?
2. Nature of surface, smooth or rough
What is Newtons second law?
States that acceleration is produced when an unbalanced force acts on an object.
How much gravity an object has depends on it's_____.
Mass
What is an objects speed if it has no speed?
Zero speed.
Force is equal to mass times what?
Acceleration
What are the factors affecting friction on an object in a fluid?
1. Speed of the object with respect to the fluid
2. Shape of the object
3. The nature of the fluid
What is Newtons third law?
For every action there is an equal and opposite reaction.
When will gravity be the strongest?
The closer you are to an object.
What is an object's speed if it is a fast moving object?
High speed.
Theoretically, if there were no forces acting on an object, and the object was moving in a particular direction at 5 m/s, what would eventually happen?
It will continue going the same speed.
Give two ways of increasing and reducing friction?
1. Making a rough surface
2. Increasing applied force.
How long will an object remain at rest, according to Newton's First Law of Motion?
As long as there are unbalanced forces acting on it.
What is the cause of gravity?
It's caused by the uneven distribution of mass.
What is the formula for speed?
Distance over Time
If an object is at rest on a flat surface, there is always gravity pulling down and the normal force pushing up. Which force is greater?
They are both equal.