Understanding Forces and Newton's Laws

What is Newton's First Law of Motion?

• An object will remain at rest or in uniform motion unless acted upon by an external force.

• An object will change direction only if a force is applied.

• An object in motion will eventually stop without any force.

• An object will accelerate if no force is applied.

Provide an example of Newton's First Law in everyday life.

• A book resting on a table remains at rest until a force acts on it.

• A car in motion will stop moving without any force applied.

• A ball thrown in the air will continue to rise indefinitely.

• A person standing still will start walking on their own.

A car is moving at a constant speed of 60 km/h. What will happen to the car if no external forces act on it?

• The car will turn left without any input.

• The car will stop immediately.

• The car will continue to move at 60 km/h.

• The car will accelerate to 80 km/h.

What is the formula for calculating force according to Newton's Second Law?

• F = m / a

• F = m - a

• F = m * a

• F = m + a

If a 5 kg object is subjected to a force of 20 N, what is its acceleration?

• 8 m/s²

• 4 m/s²

• 10 m/s²

• 2 m/s²

Explain Newton's Third Law of Motion with an example.

• A ball rolls down a hill due to gravity.

• A car accelerates when the driver presses the gas pedal.

• A person pushes a wall and the wall moves towards them.

• An example of this is when a person jumps off a small boat. As the person pushes down on the boat (action), the boat pushes them upward (reaction), causing the boat to move backward.

If a person pushes a wall with a force of 50 N, what force does the wall exert back on the person?

• 50 N

• 100 N

• 75 N

• 25 N

Calculate the net force acting on an object if two forces of 10 N and 15 N are acting in the same direction.

• 20 N

• 15 N

• 5 N

• 25 N

An object has a mass of 10 kg and is accelerating at 2 m/s². What is the net force acting on the object?

• 15 N

• 25 N

• 10 N

• 20 N

What happens to the motion of an object if the net force acting on it is zero?

• The object accelerates in the direction of the net force.

• The object will eventually come to a stop.

• The object remains at rest or moves with constant velocity.

• The object will start spinning uncontrollably.