1.
A combination of all the forces acting on an object is referred to as the
Correct Answer
A. Net force
Explanation
The combination of all the forces acting on an object is referred to as the net force. This term represents the overall effect of all the individual forces on an object's motion. It takes into account both the magnitude and direction of each force, resulting in a single resultant force that determines the object's acceleration or deceleration. The net force can be calculated by summing up all the individual forces acting on an object.
2.
When we measured force in our labs we used a piece of lab equipment called a ___________
Correct Answer
A. Spring scale
Explanation
A spring scale is a piece of lab equipment commonly used to measure force. It consists of a spring attached to a hook, and as force is applied to the hook, the spring stretches or compresses. The amount of stretch or compression is directly proportional to the force being applied. By measuring the displacement of the spring, we can determine the force being exerted. Therefore, a spring scale is the appropriate equipment for measuring force in a lab setting.
3.
What happens when two forces act in the same direction?
Correct Answer
A. They add together
Explanation
When two forces act in the same direction, they add together. This means that their magnitudes are combined, resulting in a larger overall force. The direction of the resultant force is the same as the original forces.
4.
Weight is the force of ____________ on an object at the surface of a planet (like Earth).
Correct Answer
A. Gravity
Explanation
Weight is the force of gravity on an object at the surface of a planet (like Earth). Gravity is the natural force that attracts objects towards each other. On Earth, the gravitational force pulls objects towards the center of the planet, giving them weight. Weight is a measure of the force exerted on an object due to gravity. Therefore, gravity is the correct answer to this question.
5.
When the only force acting on a falling object is gravity, the object is said to be in _____
Correct Answer
A. Free fall
Explanation
When the only force acting on a falling object is gravity, the object is said to be in free fall. This means that the object is not experiencing any other forces, such as air resistance, which could slow it down or change its motion. In free fall, the object is only influenced by the force of gravity, causing it to accelerate downwards at a constant rate. This term is commonly used to describe the motion of objects falling near the surface of the Earth.
6.
A push or a pull in science is referred to as a ___
Correct Answer
A. Force
Explanation
In science, a push or a pull is referred to as a force. Force is a fundamental concept in physics that describes the interaction between objects and can cause them to accelerate, decelerate, or change direction. It is measured in units called Newtons and can be exerted through direct contact or at a distance. Force is responsible for the motion and behavior of objects, and understanding it is crucial in understanding the laws of motion and other principles in physics.
7.
The force that results from two surfaces rubbing together is referred to as ________
Correct Answer
A. Friction
Explanation
Friction refers to the force that occurs when two surfaces rub against each other. It is the resistance encountered when attempting to move one object over another. Friction is caused by the irregularities in the surfaces, which interlock and create resistance. This force is present in various daily activities, such as walking, driving, or even writing with a pen. Magnetism, gravity, and elasticity are unrelated to the force that arises from two surfaces rubbing together.
8.
Two things determine the strength of friction, how hard the surfaces are pushed together and,,,
Correct Answer
A. The types of surfaces involved
Explanation
The strength of friction is determined by the types of surfaces involved. Different surfaces have different levels of roughness and texture, which can affect the amount of friction between them. Surfaces with more roughness and texture will generally have a stronger frictional force compared to smoother surfaces. Therefore, the types of surfaces involved play a crucial role in determining the strength of friction.
9.
Magnetic force surrounds a magnet and is caused by ...
Correct Answer
A. Electric charges in the atoms that make up the magnet lining up in the same way
Explanation
The correct answer is electric charges in the atoms that make up the magnet lining up in the same way. When a magnet is formed, the electrons in its atoms align in a specific manner, creating a magnetic field. This alignment of charges generates a force that attracts or repels other magnetic materials. It is this arrangement of charges in the atoms that gives rise to the magnetic force surrounding a magnet.
10.
If something returns to its original shape after it is squeezed or stretched it has .....
Correct Answer
A. Elastic force
Explanation
When something returns to its original shape after being squeezed or stretched, it indicates the presence of elastic force. Elastic force is the force that causes an object to return to its original shape or size when the external force is removed. This force is commonly observed in materials like rubber bands or springs, which can be stretched or compressed and then return to their original form.
11.
We know that the Earth acts as a large bar magnet because...
Correct Answer
A. We see tiny magnetic minerals lined up to with the Earth's magnetic field in rocks of all ages
12.
Compasses work because...
Correct Answer
A. Its needle is a small magnet and it is pulled by Earth's magnetic field to point to the North Pole
Explanation
Compasses work because their needle is a small magnet and it is pulled by Earth's magnetic field to point to the North Pole. The Earth has a magnetic field that acts like a giant magnet, with one end near the North Pole and the other end near the South Pole. The needle of the compass aligns itself with the Earth's magnetic field, causing it to point north. This allows people to determine their direction and navigate accurately using a compass.
13.
The SI unit of measure for the strength of a force is _____
Correct Answer
A. Newton
Explanation
The SI unit of measure for the strength of a force is the Newton. This unit is named after Sir Isaac Newton, who made significant contributions to the field of physics and formulated the laws of motion. The Newton is defined as the force required to accelerate a one-kilogram mass by one meter per second squared. It is widely used in various scientific and engineering disciplines to quantify and describe forces.
14.
Gravity is a force that ______ objects with mass toward __________
Correct Answer
A. Pulls; each other
Explanation
Gravity is a force that pulls objects towards each other. This is because every object with mass exerts a gravitational pull on other objects. The strength of this pull depends on the mass of the objects and the distance between them. Therefore, gravity is responsible for keeping objects, such as planets and moons, in orbit around each other and for keeping us grounded on Earth.
15.
Magnets stick to materials made out of...
Correct Answer
D. All of the above
Explanation
Magnets stick to materials made out of iron, nickel, and cobalt. Additionally, magnets can also stick to materials made out of other metals such as steel. Therefore, the correct answer is "all of the above" because it encompasses all the materials mentioned in the options.