Worksheet: Forces and their Effects | IGCSE Cambridge Science for Year 6 - Class 6 PDF Download

Multiple Choice Questions (MCQs)

Q1. What is the unit for measuring weight?

A) Kilogram (kg)

B) Meter (m)

C) Newton (N)

D) Joule (J)

Answer: C) Newton (N)

Explanation: Weight is a force, and the unit for measuring force is the Newton (N), not the Kilogram (kg) which measures mass.

Q2. What factor does not affect the gravitational force between two objects?

A) Distance between them

B) Their colors

C) Their masses

D) None of the above

Answer: B) Their colors

Explanation: Gravitational force is affected by mass and distance, not by properties like color.

Q3. Which of the following scenarios best describes free fall?

A) A leaf falling from a tree

B) A skydiver before opening the parachute

C) Driving down a steep hill

D) Floating in water

Answer: B) A skydiver before opening the parachute

Explanation: Free fall occurs when the only force acting on an object is gravity, as with a skydiver before the parachute is deployed.

Q4. If an astronaut in orbit feels weightless, it is because:

A) There is no gravity in space

B) Gravity is cancelled out by other forces

C) They are in continuous free fall around the Earth

D) Their mass becomes zero

Answer: C) They are in continuous free fall around the Earth

Explanation: Astronauts feel weightless not because there is no gravity, but because they are in a state of continuous free fall, effectively orbiting around the Earth.

Q5. Which design feature does not help reduce air resistance in vehicles?

A) Streamlined shape

B) Rough surface textures

C) Rounded edges

D) Smaller front area

Answer: B) Rough surface textures

Explanation: Rough surfaces increase drag; streamlined shapes, rounded edges, and smaller front areas help reduce air resistance.

Fill in the Blanks

Q1. Gravity is a force that all objects with __________ exert towards each other.

Answer: mass

Explanation: Gravity is a force exerted by all objects that have mass.

Q2. The weight of an object can be calculated by multiplying its mass by the gravitational field strength, represented by __________.

Answer: g

Explanation: Weight is calculated using the formula 

Weight =mass×𝑔

Q3. In a vacuum, objects fall at the same rate because there is no __________ to affect them.

Answer: air resistance

Explanation: In a vacuum, the absence of air means no air resistance, so all objects fall at the same rate regardless of their weight.

Q4. A __________ meter is used to measure weight in newtons.

Answer: Newton

Explanation: A Newton meter is specifically designed to measure forces including weight, which is expressed in newtons.

Q5. The concept of __________ is observed when two solid surfaces move against each other, slowing down movement.

Answer: friction

Explanation: Friction occurs between two moving solid surfaces, opposing motion and eventually stopping it.

True/False

Q1. Weightlessness means there is no gravity acting on the object. 

Ans: (False)

Explanation: Weightlessness typically means the effect of gravity is not felt, but gravity is still acting on the object, as in the case of astronauts in orbit.

Q2. The mass of an object changes depending on its location.

Ans:  (False)

Explanation: Mass is a constant property and does not change with location, unlike weight which can change due to varying gravitational forces.

Q3. Air resistance increases with the speed of the object moving through the air. 

Ans: (True)

Explanation: As the speed of an object increases, the air resistance acting against it also increases.

Q4. A larger surface area decreases the air resistance experienced by an object.

Ans:  (False)

Explanation: A larger surface area actually increases the air resistance experienced by an object.

Q5. Gravity on the Moon is about 1/6th that of Earth's gravity. 

Ans: (True)

Explanation: The Moon's gravitational force is significantly weaker than Earth's, approximately one-sixth.

Match the Columns

Column A           Column B

A) Weight                         Opposes motion through air

B) Friction                         Force due to gravity on mass

C) Free Fall                      Occurs only under the influence of gravity

D) Air Resistance         Force between moving solid surfaces

E) Gravitational  Field Strength       Varies with location and altitude

Matches

A-2) Weight is the force due to gravity acting on mass.

B-4) Friction is the force occurring between moving solid surfaces.

C-3) Free fall occurs when only gravity influences an object's motion.

D-1) Air resistance opposes motion through air.

E-5) Gravitational field strength can vary depending on location and altitude.