1. When two magnets are brought close to each other, and they attract each other, what can you say about their poles?
a) Both magnets have like poles.
b) Both magnets have unlike poles.
c) The information is insufficient to determine their interaction.
d) Magnets cannot attract each other.
Answer: b) When two magnets attract each other, it means they have opposite poles. Like poles repel each other, so if the magnets were to have like poles, they would push each other away instead of attracting.
2. Ellie and Joel want to demonstrate the concept of buoyant force. Which of the following experiment should they conduct?
a) Dropping a rock into a bucket of water
b) Rubbing a comb on a sweater and attracting small pieces of paper
c) Pushing a car to make it move
d) Holding a balloon filled with air and letting it go
Answer: a) By dropping a rock into a bucket of water, Ellie and Joel can observe the buoyant force in action. This experiment demonstrates how objects can float or sink based on the balance between their weight and the buoyant force exerted by the fluid they are immersed in.
3. Consider the two statements given below and choose the correct option:
Statement 1: Frictional force always has negative effects.
Statement 2: The presence of force is necessary to initiate motion but not to maintain it.
a) Statement 1 is correct and Statement 2 is wrong
b) Statement 1 is wrong and Statement 2 is correct
c) Both statements are correct
d) Both statements are wrong
Answer: b) Frictional force does not always have negative effects. It has several advantageous applications, such as enabling us to walk, write, and grip objects.
Statement 2 is correct as an initial force is required to initiate motion, but once an object is in motion, it can continue moving with no external force.
4. Two objects with opposite charges are brought near each other. Select the correct option about how they would react.
a) They attract each other
b) They repel each other
c) They remain stationary
d) They combine to form a larger charge
Answer: a) When two objects with opposite charges are brought near each other, they will experience an attractive force. Opposite charges attract each other, causing the objects to come closer together.
5. What happens when the buoyant force is greater than the weight of an object?
a) The object sinks
b) The object remains suspended
c) The object floats
d) The object moves sideways
Answer: c) When the buoyant force exerted on an object is greater than its weight, the object will experience an upward force that is greater than the downward force of gravity. As a result, the object will float on the surface of the fluid, supported by the buoyant force.
FAQs
1. What is Force?
A push or pull that has the power to change an object's shape, speed, or direction is known as force.
2. What is gravitational force, and how does it work?
Gravitational force is the force of attraction between two objects with mass. It's what keeps us grounded on Earth and makes objects fall when dropped.
3. What units are used for measuring force, and how do we measure it?
Newtons (N) are used to measure force. Spring scales and force gauges are common instruments used in force measurement.
4. What is friction, and how does it affect motion?
Friction is a contact force that opposes the motion of objects in contact with each other. It can slow down or stop moving objects and is important for walking, driving, and more.
5. What are the two main types of forces we encounter in everyday life?
The two main types of forces are contact forces, which involve direct physical contact, and non-contact forces, which can act at a distance without touching.
