Topic 5 Forces Flashcards
What is the definition of force?
A force is a push or pull acting on an object.
What is the unit of force in the SI system?
The unit of force is the Newton (N).
True or False: Force is a vector quantity.
True
Fill in the blank: The formula for calculating force is _____ = mass × acceleration.
force
What are Newton’s three laws of motion?
- An object at rest stays at rest; 2. F = ma; 3. For every action, there is an equal and opposite reaction.
What does the term ‘net force’ refer to?
The net force is the vector sum of all forces acting on an object.
Multiple Choice: Which of the following is NOT a type of force? A) Gravitational B) Frictional C) Thermal D) Electromagnetic
C) Thermal
What is gravitational force?
Gravitational force is the attraction between two masses.
True or False: Friction always acts in the direction of motion.
False
Fill in the blank: The force that opposes the motion of an object is called _____ force.
frictional
What is the formula for calculating weight?
Weight = mass × gravitational field strength (W = mg).
What is the gravitational field strength on Earth?
The gravitational field strength on Earth is approximately 9.81 N/kg.
Multiple Choice: Which force is responsible for keeping planets in orbit? A) Friction B) Gravitational C) Tension D) Magnetic
B) Gravitational
What is tension force?
Tension force is the force transmitted through a string, rope, or cable when it is pulled tight.
True or False: The direction of friction force is always opposite to the direction of motion.
True
What is the difference between static and kinetic friction?
Static friction prevents motion between two surfaces, while kinetic friction acts when surfaces are sliding past each other.
Fill in the blank: The force that acts at a distance without direct contact is called _____ force.
non-contact
What is air resistance?
Air resistance is a type of frictional force that opposes the motion of an object through air.
What happens to the net force when balanced forces act on an object?
The net force is zero.
Multiple Choice: What is the effect of unbalanced forces on an object? A) It remains at rest B) It changes its motion C) It does not accelerate D) It stays in equilibrium
B) It changes its motion
What is the principle of moments?
The principle of moments states that for an object in equilibrium, the sum of clockwise moments about any point equals the sum of anti-clockwise moments about that point.
True or False: A larger mass will always experience a larger gravitational force.
True
Fill in the blank: The force required to change the motion of an object is called _____ force.
net
What is the relationship between force, mass, and acceleration as per Newton’s second law?
Force is directly proportional to mass and acceleration (F = ma).
What type of force is experienced by objects in free fall?
Gravitational force.
Multiple Choice: Which of the following can change the direction of an object’s motion? A) Mass B) Force C) Energy D) Speed
B) Force
