1. What is the unit of force?
1. What is the unit of force?
Explanation:
The unit of force is the Newton (N), named after Sir Isaac Newton, which is defined as the amount of force required to accelerate a mass of one kilogram at a rate of one meter per second squared. In other words, a force of one newton will impart an acceleration of one meter per second squared on a one-kilogram object.
2. Give one example where force moves a stationary object.
2. Give one example where force moves a stationary object.
Explanation:
One example is when you push a box on a flat surface. If a box is stationary on the ground, it will remain at rest until an external force is applied to it. When you push the box with a force greater than the force of friction between the box and the ground, the box will start to move.
3. Give one example where force stops a moving object.
3. Give one example where force stops a moving object.
Explanation:
When you apply brakes to a moving car. When a car is moving, it possesses kinetic energy due to its motion. In order to stop the car, a force must be applied in the opposite direction to the direction of its motion. When you apply the brakes, the brake pads apply a force to the wheels, which creates a frictional force that opposes the direction of motion of the car.
4. What is force?
4. What is force?
Explanation:
Force is an influence that can cause an object to accelerate, deform or change its state of motion. More specifically, force is a vector quantity, which means it has both magnitude and direction.
5. Does liquid exert pressure in all directions?
5. Does liquid exert pressure in all directions?
Explanation:
Yes, that is true. This is because liquids, like gases, are fluids and do not have a fixed shape, but instead take the shape of their container. When a liquid is contained in a vessel, each particle of the liquid is free to move and will experience the force of gravity pulling it downward.
6. Why does the shape of the toothpaste tube change when we squeeze it?
6. Why does the shape of the toothpaste tube change when we squeeze it?
Explanation:
When we squeeze the tube, we apply an external force to the toothpaste inside, which causes it to flow out of the nozzle. As the toothpaste flows out, the pressure inside the tube decreases, which causes the tube to collapse inwards.
7. What can bring change in the state of motion of an object?
7. What can bring change in the state of motion of an object?
Explanation:
When an object is acted upon by an unbalanced force, it can experience a change in its state of motion. If the force is in the same direction as the object's motion, it can cause the object to speed up. The force of gravity can cause an object to accelerate towards the ground. If an object is dropped from a height, gravity will cause it to accelerate towards the ground at a rate of 9.8 meters per second squared.
8. Which force can be used to gather iron pins scattered on the floor?
8. Which force can be used to gather iron pins scattered on the floor?
Explanation:
It is the magnetic force. This is a common technique used to collect scattered iron pins or other small metal objects such as screws, nails, or paperclips. It is particularly useful when the pins or other metal objects are scattered in hard-to-reach areas or in areas where it would be difficult to pick them up by hand.
9 Which forces do the animals apply while moving, chewing and doing other activities?
9 Which forces do the animals apply while moving, chewing and doing other activities?
Explanation:
Animals use their muscles to create force and generate movement. The contraction of muscles can produce both pushing and pulling forces that allow animals to move their limbs and body. Friction is the force that opposes motion between two surfaces in contact.
10. Which force is responsible for raising our body hair when we try to take off a terylene or polyester shirt in the dry weather?
10. Which force is responsible for raising our body hair when we try to take off a terylene or polyester shirt in the dry weather?
Explanation:
It is the electrostatic force. When we try to take off a terylene or polyester shirt in dry weather, the friction between the shirt and our skin can generate a static charge. This static charge can then cause the individual hairs on our skin to stand up, as the charge attracts or repels the hair strands.
11. Write one example where force changes the speed of a moving object.
11. Write one example where force changes the speed of a moving object.
Explanation:
It is a car accelerating on a level road. When the driver presses on the accelerator pedal, the engine produces a force that is transmitted to the wheels through the transmission and drivetrain. This force causes the car to accelerate and increases its speed. If the driver then releases the accelerator pedal, the force on the wheels is reduced, causing the car to slow down and decrease its speed.
12. Why does a boat come to rest when we stop rowing it?
12. Why does a boat come to rest when we stop rowing it?
Explanation:
When we stop rowing, the force on the boat is removed. According to Newton's first law of motion, an object at rest or in motion will remain in its state of rest or motion unless acted upon by an external force. In the case of the boat, the external force that was propelling it forward has been removed, and there is no longer any force acting on the boat to keep it moving.
13. Write any two applications of atmospheric pressure in our everyday life.
13. Write any two applications of atmospheric pressure in our everyday life.
Explanation:
When we drink a liquid through a straw, we create a vacuum inside the straw by sucking the air out of it. The atmospheric pressure outside the straw then pushes the liquid up the straw and into our mouth. When we inflate a tire, we use a pump to increase the pressure of the air inside the tire. This increase in pressure allows the tire to support the weight of the vehicle and provide a smoother ride.
14. What is pressure?
14. What is pressure?
Explanation:
Pressure is defined as the amount of force applied per unit area. In other words, it is the force exerted over a given area. Pressure can be represented mathematically as P = F/A, where P is the pressure, F is the force, and A is the area over which the force is applied.
15. Give one practical application of magnetic force.
15. Give one practical application of magnetic force.
Explanation:
Electric motors use magnetic fields to convert electrical energy into mechanical energy, which can be used to power a variety of machines and devices.
16. Give one example from daily life where force changes the shape of an object.
16. Give one example from daily life where force changes the shape of an object.
Explanation:
When we apply force to a sponge by squeezing it, the shape of the sponge changes as it compresses and the air pockets inside it shrink. The force we apply causes the sponge to deform and take on a new shape, and the amount of deformation depends on the amount of force applied.
17. Explain why snow shoes stop you from sinking into snow.
17. Explain why snow shoes stop you from sinking into snow.
Explanation:
By wearing snowshoes, a person's weight is spread out over a larger area, which reduces the pressure that is exerted on the snow. This allows them to walk on top of the snow without sinking in, as the snow can support their weight more easily.
18. What happens to the springs fixed to the seat of a bicycle when we sit on it?
18. What happens to the springs fixed to the seat of a bicycle when we sit on it?
Explanation:
As we sit on the bicycle seat, our weight is transferred to the springs, causing them to compress and bend. This compression stores potential energy in the springs, which is released when we hit bumps or uneven terrain. The springs then expand back to their original shape, absorbing the shock and smoothing out the ride for the rider.
19. What is meant by atmospheric pressure?
19. What is meant by atmospheric pressure?
Explanation:
Atmospheric pressure refers to the force per unit area exerted by the weight of the Earth's atmosphere on any object placed on or within it. The Earth's atmosphere is made up of a mixture of gases, primarily nitrogen and oxygen, that extend from the surface of the Earth to the edge of space.
20. What do you mean by magnitude?
20. What do you mean by magnitude?
Explanation:
Magnitude refers to the size, quantity, or intensity of something. It is a measure of the scale or extent of a physical quantity, such as the length of an object, the strength of a force, the brightness of a star, or the intensity of an earthquake.
21. What is muscular force?
21. What is muscular force?
Explanation:
Muscular force refers to the force exerted by the muscles of the body. Muscles are the primary organs of the muscular system and are responsible for producing movement in the body by contracting and exerting force on bones, organs, and other tissues.
22. What is contact force ?
22. What is contact force ?
Explanation:
Contact force is a type of force that arises when two objects physically touch or interact with each other. When two objects come into contact, there is usually a force that is exerted by one object on the other, and this force is called a contact force.
23. What do you mean by the term atmosphere?
23. What do you mean by the term atmosphere?
Explanation:
The atmosphere refers to the layer of gases that surrounds the Earth and is held in place by the Earth's gravity. It extends from the Earth's surface up to about 10,000 kilometers. The atmosphere is divided into several layers based on temperature changes with altitude. The lowest layer is called the troposphere, which is where most of the Earth's weather occurs and where air temperature decreases with increasing altitude.
24. How do fluids exert pressure?
24. How do fluids exert pressure?
Explanation:
Fluids exert pressure because of the random motion of their molecules or atoms. The motion of these particles creates a force that is exerted on any surface that they come into contact with, and this force is distributed evenly over the surface. The pressure exerted by a fluid on a surface is defined as the force per unit area of the surface and is expressed in units of Pascals (Pa), which is equivalent to Newtons per square meter (N/m²).
25. A force of 1000 N is applied on an area of 5 m2. Compute pressure being applied on the area?
25. A force of 1000 N is applied on an area of 5 m2. Compute pressure being applied on the area?
Explanation:
Given:
Force = 1000 N, Area = 5 m2
∴ Pressure = Force/Area
= 1000/5
= 200pa.
26. Which force is responsible for downward movement of parachutes?
26. Which force is responsible for downward movement of parachutes?
Explanation:
It is gravity. When a parachute is deployed, it increases the air resistance or drag acting on the parachute and its wearer, which opposes the force of gravity and slows down their descent.
27. Two thermocol balls held close to each other move away from each other. When they are released, name the force which might be responsible for this phenomenon. Explain.
27. Two thermocol balls held close to each other move away from each other. When they are released, name the force which might be responsible for this phenomenon. Explain.
Explanation:
Thermocol balls are made up of expanded polystyrene, which is an insulator and does not conduct electricity. When two thermocol balls are rubbed together, they can become electrically charged through a process called triboelectric charging. This happens because the rubbing transfers electrons between the surfaces, causing one to become negatively charged and the other positively charged.
28. How does an applied force change the speed of an object?
28. How does an applied force change the speed of an object?
Explanation:
An applied force can change the speed of an object by changing its velocity, which is a measure of the object's speed and direction. If a force is applied to an object in the direction of its motion, the object will experience an acceleration in the same direction, which will cause an increase in its speed.
29. What is the similarity between electrostatic and magnetic forces?
29. What is the similarity between electrostatic and magnetic forces?
Explanation:
The similarity between electrostatic and magnetic forces is that they are both fundamental forces of nature that act between objects without direct physical contact. Both electrostatic and magnetic forces are long-range forces that can act over large distances. They are also related to the properties of charged particles, although in different ways.
30. What are the effects of force on an object?
30. What are the effects of force on an object?
Explanation:
Force can cause an object to start moving from rest, speed up, slow down, or change direction. This is because force produces acceleration, which is the rate of change of velocity. Force can also cause an object to change its shape or size. This is known as deformation, and can occur in solids, liquids, and gases.
31. Define the different types of forces.
31. Define the different types of forces.
Explanation:
Contact and non-contact forces are two broad categories of forces that exist in the natural world. Contact forces are forces that act on an object when it is in direct contact with another object. These forces arise from the interaction between the two surfaces in contact and can either be attractive or repulsive. Non-contact forces are forces that act on an object without the need for direct physical contact. These forces can act over a distance and are typically associated with fields or other physical phenomena.
32. Why does water come out more slowly from an upstairs tap than from a similar tap downstairs?
32. Why does water come out more slowly from an upstairs tap than from a similar tap downstairs?
Explanation:
It is due to the effects of gravity and water pressure. When water is pumped into a building or supplied from a water tower, it enters at a high pressure. This high pressure allows the water to flow easily through pipes and up to higher levels of the building.
33. Why are we not crushed by atmospheric pressure?
33. Why are we not crushed by atmospheric pressure?
Explanation:
Because our bodies, and the objects around us, are in equilibrium with the pressure exerted by the atmosphere. The Earth's atmosphere is made up of air molecules that are constantly colliding and exerting a force on objects in their path. However, this pressure is evenly distributed in all directions and balanced by the pressure inside our bodies and the objects around us.
34. What is frictional force?
34. What is frictional force?
Explanation:
Frictional force is a force that opposes motion or attempted motion between two surfaces that are in contact with each other. It is caused by the roughness or irregularities of the surfaces in contact, which resist the relative motion between them.
35. Why does a sharp knife cut better than a blunt knife?
35. Why does a sharp knife cut better than a blunt knife?
Explanation:
Because it requires less force to cut through the material, and the force is applied over a smaller area. A sharp knife has a thin, narrow edge that can easily slice through the material, while a blunt knife has a thicker edge that crushes and tears the material, requiring more force and resulting in a less precise cut.
36. A blacksmith hammers a hot piece of iron while making a tool. How does the force due to hammering affect the piece of iron?
36. A blacksmith hammers a hot piece of iron while making a tool. How does the force due to hammering affect the piece of iron?
Explanation:
The force of the hammer shapes the iron into the desired form, as the blacksmith hammers the iron into the desired shape and size. The force of the hammering heats up the iron even further, making it more malleable and easier to shape.
37. What do you understand by state of Motion?
37. What do you understand by state of Motion?
Explanation:
The state of motion refers to the movement or lack of movement of an object. An object can be in one of three states of motion: at rest, in uniform motion, or accelerating.
38. Explain why the tip of a sewing needle is sharp.
38. Explain why the tip of a sewing needle is sharp.
Explanation:
Because it needs to penetrate through fabric with minimal resistance, while causing the least damage to the fabric. The sharp point of the needle helps to pierce through the fabric fibers easily, reducing the amount of force required to push the needle through.
39. Explain why, porters place a thick, round piece of cloth on their heads when they have to carry heavy loads.
39. Explain why, porters place a thick, round piece of cloth on their heads when they have to carry heavy loads.
Explanation:
The tip of a sewing needle is sharp because it needs to penetrate through fabric with minimal resistance, while causing the least damage to the fabric. The sharp point of the needle helps to pierce through the fabric fibers easily, reducing the amount of force required to push the needle through.
40. Why are the straps of school bags made broader?
40. Why are the straps of school bags made broader?
Explanation:
When carrying a heavy backpack, the weight of the bag can cause strain on the shoulders, neck, and back. By using broader straps, the weight of the bag is distributed more evenly across a larger area of the shoulders and back, reducing the pressure on any one particular point. This can help to prevent soreness, fatigue, and injury from carrying the bag for extended periods of time.
