Science reviewer part 2🧬🔬

What is friction?

Friction is the resistance that one surface or object encounters when moving over another.

How does friction affect motion?

Friction slows down or stops the motion of an object by converting kinetic energy to thermal energy.

What is gravity?

Gravity is the force that attracts a body toward the center of the earth, or toward any other physical body having mass.

How does gravity affect objects in motion?

Gravity pulls objects downward, influencing their speed and direction of fall.

What are the different forms of energy?

The main forms of energy include kinetic, potential, thermal, chemical, electrical, and nuclear energy.

What is kinetic energy?

Kinetic energy is the energy of an object due to its motion.

What is potential energy?

Potential energy is the energy stored in an object based on its position or configuration.

What are simple machines?

Simple machines are tools that make work easier by allowing us to apply force in a more efficient manner.

Name the six types of simple machines.

The six types of simple machines are the lever, wheel and axle, pulley, inclined plane, screw, and wedge.

How do simple machines help in work efficiency?

Simple machines reduce the amount of effort needed to accomplish a task by changing the direction or magnitude of the force applied.

What factors influence friction between surfaces?

Factors include the types of materials in contact, surface roughness, and the normal force.

How does increased mass affect the force of gravity?

Increased mass results in a stronger gravitational pull between two objects.

What is the role of air resistance in friction?

Air resistance acts against the motion of objects moving through the air, affecting their speed.

How does friction contribute to wear and tear on objects?

Friction causes material to gradually wear down, reducing the lifespan of objects.

What is mechanical energy?

Mechanical energy is the sum of potential and kinetic energy in an object.

How does temperature affect the properties of a material?

Temperature changes can alter the strength and elasticity of a material, impacting friction.

What is the difference between static and kinetic friction?

Static friction prevents motion in stationary objects, while kinetic friction acts on moving objects.

How do inclined planes reduce the force needed to lift objects?

Inclined planes spread the work over a longer distance, which reduces the required force.

What type of energy does a compressed spring store?

A compressed spring stores potential energy.

How do pulleys assist in lifting heavy loads?

Pulleys change the direction of the force needed, making lifting easier.

How is energy conserved in a pendulum?

In a pendulum, kinetic energy converts to potential energy and vice versa while conserving total energy.

What is the formula for gravitational potential energy?

Gravitational potential energy is calculated as PE = mgh, where m is mass, g is acceleration due to gravity, and h is height.

How does the surface texture affect friction?

Smoother surfaces create less friction than rough surfaces due to less interaction between molecules.

What happens to an object's kinetic energy as it comes to a stop?

As an object comes to a stop, its kinetic energy is transformed to thermal energy, often due to friction.

What is hydraulic power in simple machines?

Hydraulic power uses fluid pressure to move objects more easily, operating like a lever.

How do gears function as simple machines?

Gears transmit force and change the direction or speed of motion in machines.

What does work input equal in a simple machine?

Work input equals work output plus any losses due to friction.

How does friction affect the efficiency of machines?

Friction reduces efficiency by converting some energy into heat rather than useful work.

What is an example of kinetic energy being converted to potential energy?

A ball thrown upwards converts its kinetic energy to potential energy as it rises.

What device uses both friction and gravity to function?

A brake system uses friction to slow down or stop a vehicle by converting kinetic energy into heat.