Forces Flashcards
What is a force?
A force is a push or a pull exerted on an object.
Forces can vary in size and direction.
What units are used to measure force?
Newton (N)
The unit is named after Sir Isaac Newton, who formulated the laws of motion.
What happens when you gently push your hands against a partner’s hands?
You observe an exertion of force in both directions.
This demonstrates the concept of action and reaction forces.
Fill in the blank: A force can be described as a _______ or a pull.
push
Forces can act on objects in various ways.
What forces act on you even when standing still?
- Gravity
- Air particles hitting your body
- Normal force from the ground
These forces are constantly at work.
True or False: Forces usually act alone.
False
Forces often act in pairs, demonstrating action and reaction.
What can forces change in an object?
Forces can change the shape of an object, cause it to move, cause a moving object to stop or change its direction.
Examples include flattening putty, moving a cart, and hitting a ball.
True or False: Forces can be seen directly.
False
Forces themselves cannot be seen, but their effects on objects can be observed.
What are the two broad categories of forces?
Contact forces and non-contact forces
Define tensile force.
Something being stretched
What are contact forces?
Forces that result when two objects are touching each other
Provide examples of contact forces.
- Tensile force
- Compression force
- Friction force
What is a compression force?
When something is squashed
What is friction force?
A force that resists motion and causes a heating effect
What are non-contact forces also known as?
Field forces
What are examples of non-contact forces?
- Gravitational forces
- Electrostatic forces
- Magnetic forces
Define gravitational forces.
The forces that objects have on each other due to their masses
What is the direction of the gravitational force that Earth exerts on objects?
Always downwards
What is the relationship between weight and mass?
Weight is determined by gravitational force; mass is the amount of matter in an object
How is weight measured?
In Newtons (N)
How is mass measured?
In kilograms (kg)
Does an object’s mass change regardless of its location?
No, an object’s mass does not change
What is the weight of a person on the moon compared to Earth?
1/6th of that on Earth
If an object has a weight of 600 N on Earth, what would its weight be on the moon?
100 N
What is a magnetic force?
Magnets exert a non-contact force on other magnetic materials.
Which metals are magnetic?
Iron, cobalt, and nickel are the only three magnetic metals.
What are the two ends of a magnet called?
The two ends of a magnet are known as the north pole and south pole.
What is the magnetic field?
The area around the magnet in which another object experiences a force is known as the magnetic field.
What happens when opposite poles of magnets interact?
Opposite poles will attract each other.
What happens when like poles of magnets interact?
Like poles will repel each other.
What is the effect of north poles on south poles?
North poles are attracted to south poles.
What is the effect of north poles on other north poles?
North poles will be repelled by another north pole.
How can you observe magnetic effects?
Use a bar magnet to see which objects are affected by the magnet.
What is the Earth’s magnetic field used for?
Direction and protection from Solar winds
The Earth’s magnetic field functions similarly to a bar magnet.
What are the two types of electric charges?
Positive charges and Negative charges
These charges interact with each other through electrostatic forces.
What is static electricity?
Charges that stay where you put them
Static electricity occurs when charges are placed on insulators like glass, plastic, rubber, and wood.
What materials are classified as insulators?
Glass, plastic, rubber, and wood
Insulators do not allow charges to move freely through them.
What occurs when two objects with like charges are near each other?
They will repel or push each other
This is an example of repulsive electrostatic forces.
What happens when two objects with unlike charges are near each other?
They will attract or pull each other
This is an example of attractive electrostatic forces.
Fill in the blank: Materials like glass and plastic are called _______.
insulators
