What is the Relationship Between Force and Weight?

Thread starter Northern Cardinal
Start date Oct 31, 2020
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Force Weight

In summary, force and weight are two distinct physical concepts. Force refers to the push or pull on an object, while weight is the measure of the gravitational force acting on an object. They are measured in Newtons (N) or pounds (lbs) and are directly proportional to each other. Mass plays a role in both force and weight, with force being directly proportional to mass and weight being affected by both mass and the acceleration due to gravity. Force and weight also play important roles in determining an object's motion, with the net force and gravitational pull influencing acceleration and direction of motion.

Oct 31, 2020

Northern Cardinal

Homework Statement: I need help figuring out c.

a) A 15.0-kg child is riding a playground merry-go-round that is rotating at 45.0 rpm. What centripetal force must she exert to stay on if she is 1.50 m from its center?
Correct answer: 499.649 N
b) What centripetal force does she need to stay on an amusement park merry-go-round that rotates at 3.00 rpm if she is 7.10 m from its center?
Correct answer: 10.511 N
c) Compare each force with her weight.

Relevant Equations: force from part (a) / weight = _______
force from part (b) / weight = _______

So here's what I've tried:

force from part (a) / weight = 499.649N / 15kg = 33.310
force from part (b) / weight = 10.511N / 15kg = 0.701

Apparently this wasn't correct. What am I doing wrong? I feel like I'm missing the obvious.

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Oct 31, 2020

gneill

Mentor

Mass is stated in kg. That's not weight. Weight is a force in Newtons.

Oct 31, 2020

Northern Cardinal

Thanks! I was able to figure out the correct answer.

Oct 31, 2020

gneill

Mentor

Excellent!

What is the difference between force and weight?

Force and weight are often used interchangeably in everyday language, but they have distinct meanings in the field of physics. Force is a vector quantity that describes the push or pull on an object, while weight is a measure of the force of gravity acting on an object. In other words, weight is a specific type of force that is always directed towards the center of the Earth.

How do you measure force and weight?

Force is typically measured in units of newtons (N) using a device called a force meter or scale. Weight is measured in units of mass, such as kilograms (kg) or pounds (lbs), using a balance or scale. However, it's important to note that weight is often expressed in units of newtons (N) when discussing it in the context of physics.

Do force and weight have the same units?

No, force and weight have different units. Force is measured in units of newtons (N), while weight is typically measured in units of mass, such as kilograms (kg) or pounds (lbs). However, as mentioned earlier, weight can also be expressed in units of newtons (N) when discussing it in the context of physics.

Is weight affected by gravity?

Yes, weight is affected by gravity. Weight is a measure of the force of gravity acting on an object. Therefore, the weight of an object will change depending on the strength of the gravitational field it is in. For example, an object will weigh less on the moon than it does on Earth because the moon has a weaker gravitational field.

How do force and weight relate to each other?

Force and weight are related through Newton's second law of motion, which states that force equals mass times acceleration (F=ma). In other words, the force acting on an object is equal to its mass multiplied by its acceleration. This means that the weight of an object is directly proportional to its mass, as weight is a specific type of force that is affected by the mass of an object.