Understanding Forces: Balanced vs Unbalanced

What are balanced forces?

• Forces that are equal in size and opposite in direction, resulting in no change in motion.

• Forces that are unequal and cause an object to accelerate.

• Forces that only act on stationary objects.

• Forces that always cause an object to move.

Answer explanation

Balanced forces are equal in size and opposite in direction, which means they cancel each other out and result in no change in motion. This is why the first answer choice is correct.

What are unbalanced forces?

• Forces that are equal in size and direction.

• Forces that cause an object to remain at rest.

• Forces that are unequal and cause a change in motion.

• Forces that do not affect the motion of an object.

Answer explanation

Unbalanced forces are unequal in size and direction, leading to a change in an object's motion. This contrasts with balanced forces, which keep an object at rest or in uniform motion.

Which of the following is an example of balanced forces?

• A car accelerating down a hill.

• A book resting on a table.

• A person pushing a swing.

• A ball rolling down a slope.

Answer explanation

Balanced forces occur when all forces acting on an object are equal and opposite, resulting in no movement. A book resting on a table has gravitational force balanced by the normal force from the table, making it an example of balanced forces.

Which of the following is an example of unbalanced forces?

• Two people pushing against each other with equal force.

• A child pulling a wagon forward.

• A lamp sitting on a desk.

• A box at rest on a flat surface.

Answer explanation

Unbalanced forces occur when one force is greater than another. A child pulling a wagon forward creates a net force, while the other options describe balanced forces or objects at rest.

What is one effect of unbalanced forces on an object?

• The object remains stationary.

• The object changes its speed or direction.

• The object becomes heavier.

• The object loses energy.

Answer explanation

Unbalanced forces cause an object to accelerate, which means it can change its speed or direction. This is why the correct answer is that the object changes its speed or direction.

What is one effect of balanced forces on an object?

• The object accelerates.

• The object changes direction.

• The object remains at rest or continues to move at a constant speed.

• The object gains mass.

Answer explanation

Balanced forces result in no net force acting on an object. This means the object will either remain at rest or continue to move at a constant speed, as there is no change in its state of motion.

If a person is pushing a stationary car with a force of 200 N to the right and another person is pushing it with a force of 200 N to the left, what type of forces are acting on the car?

• Unbalanced forces

• Balanced forces

• Frictional forces

• Gravitational forces

Answer explanation

The forces are balanced because the two people are pushing with equal force in opposite directions (200 N right and 200 N left), resulting in no net force acting on the car.

When a soccer ball is kicked, what type of forces are acting on it after it leaves the player's foot?

• Balanced forces

• Unbalanced forces

• Static forces

• Magnetic forces

Answer explanation

After a soccer ball is kicked, it experiences unbalanced forces such as gravity pulling it down and air resistance acting against its motion. These forces cause the ball to accelerate and change direction, confirming the choice of unbalanced forces.

Which scenario best illustrates balanced forces?

• A skateboarder pushing off the ground to gain speed.

• A tug-of-war game where both teams pull with equal force.

• A car speeding up on a highway.

• A balloon rising in the air.

Answer explanation

Balanced forces occur when equal forces act in opposite directions, resulting in no change in motion. In a tug-of-war with equal pulling forces, neither team moves, illustrating balanced forces perfectly.

What happens to an object when unbalanced forces act on it?

• It stays in the same position.

• It moves in the direction of the greater force.

• It loses all its energy.

• It becomes invisible.

Answer explanation

When unbalanced forces act on an object, it accelerates in the direction of the greater force, resulting in a change in its motion.